I was thinking abut this today, and I was wondering how often one of these games fed into a good chess engine, would also end up as a draw? In other words, is it possible the some of these games could have ended in a mate....
Do most GM games end in resignation?

Most GM games end in a draw. Getting mated is considered to be extremely shameful, no one plays till checkmate. At one point it was even fashionable to resign at such (lost) positions where amateurs stared and asked what happened.
I say screw fashion. These GM's baby each other. I'm not resigning until I'm down big material with no counterchances at all.
Well, for them it's just a matter of showing their skills. That is, if one GM catches another thinking he's ok while he's totally lost, that's considered a disgrace. For this very reason GMs often play in the "I also see that you're winning" game, thus underscoring how good they are.
I always wondered if they did it to try to look good. I often see losing tactical variations in my games but I simply play them out with the hope that my opponent doesn't see one of the moves.
I wonder how different it is though when you spend 8 hours a day studying and you're a chess professional, and then you sit down across from a player you recognize as a fellow professional. When you see the clear technique or tactic that will make you lose, and they play the first few moves, it just makes sense to resign.
I just wonder if the mindset is a bit different when you're a professional player, and you consider it your job to know these things. In my tournament games I don't resign till it's very clear. And even if I go down a rook for nothing I'll play 1-2 more moves just on principal to show some fighting spirit, so I know what you mean... well, sometimes I also keep playing a few moves to let the shock of pretty much being guaranteed to lose fade a bit, so I can objectively assess just how much compensation there might be in the position.
I once had the great satisfaction of carrying out an actual checkmate of a master. I had found a forced mate in five. About two moves into it he said, "Uh-oh," but played to the bitter end. Maybe he thought that maybe I didn't see it all or might make a mistake.

Reasons Gm's resign-
1) Professional Players do not get paid by the hour.
2) Playing on in a hopeless position vs another Pro is going to make them angry and at best they might slowly torture you for the maximum amount of time. Sometimes to break an opponents spirit a pro will forcibly repeat positions to wear down their opponents will.
3) In a multi-round tournament, it makes more sense to resign and start preparing for your next opponent, then to hold out for a miracle.
4) Pride. Most games are decided by much smaller details than dropping a piece, pawn or such.
5) Once in a blue moon a master will allow themselves to be mated simply because the mate is so beautiful. This is rare though.

I enjoy reading some books on older tournaments and games, and some of them ended in "white announces mate in 5, game ended.".
But other than that, most of them seems to end in resignation before mate or heavy loss of material.
Oh yes, "And with Anderssen announcing mate in 14, the game ended," how cool is that!

I think this is the only game I saw that ended up in a modern super gm getting mated, it's from the first round of amber just a couple of days ago, and surprisingly it wasn't even blindfold, it was in severe time trouble in rapid.

I've seen it recommended by coaches that players should find a GM game where one side resigns and practice playing out the winning side against a strong computer program, like Fritz or Rybka. Thus, you'll learn the technique for the winning side.
GMs resign because they forgot how to do king and queen endings.
Hah.
In a blitz game the other day, I had a "K+R versus K" endgame, and my opponent didn't resign as I had only five seconds left on the clock. Problem is, I couldn't remember, within those five seconds, how to play this endgame, since I hadn't played it out in ages. Needless to say, I lost on time. ;D

GMs resign because they forgot how to do king and queen endings.
Hah.
In a blitz game the other day, I had a "K+R versus K" endgame, and my opponent didn't resign as I had only five seconds left on the clock. Problem is, I couldn't remember, within those five seconds, how to play this endgame, since I hadn't played it out in ages. Needless to say, I lost on time. ;D
That happened to me once either, I realised I truly have no idea about that mate. Now I'm back to watching basic mating techniques in Muller DVDs . I guess the trick is just drilling them until you can't forget, which I'm still postponing to do, because it occurs very rare. It's obviously not like you can't mate an opponent like that with a few minutes on the clock, but you need to be able to do it within 5 seconds when somebody wakes you up in the middle of the night, that's what Muller says anyway.

Because the games go into an endgame most times GMs play, it comes down to who gets the pawn advantage and can maintain it without compromising the position, such as going into a bishops of opposite color endgame or rook vs rook endgame where even the side with the extra pawn can be held to a draw.
That happened to me once either, I realised I truly have no idea about that mate. Now I'm back to watching basic mating techniques in Muller DVDs . I guess the trick is just drilling them until you can't forget, which I'm still postponing to do, because it occurs very rare. It's obviously not like you can't mate an opponent like that with a few minutes on the clock, but you need to be able to do it within 5 seconds when somebody wakes you up in the middle of the night, that's what Muller says anyway.
Sounds like great advice. The area of greatest neglect in my game is certainly the endgame.
In the game in question, I somehow couldn't recall the "box method" to force the king to the edge, and just kept checking the king over and over, thinking, "Wow, this is harder than I remember." :-) I eventually remembered it after my flag fell.

Here's an example of a victory by checkmate in one of the most famous games ever played AND it's still considered contemporary. Byrne does not forfeit simply because he recognized how beautiful of a game Fischer played and wanted to allow Fischer the satisfaction of a full victory and leave a complete game for study in the future.
It's difficult for us woodpushers to understand how good the REALLY good are ("He plays a game with which I am not familiar." Bobby Jones of Jack Nacklaus) and so we play on in situations that -- to an expert -- have lost all charm, all intrigue, all mystery. To the expert, who can see all the way to the end, there's really no point in just pushing the pieces around the board; he (or she) has already mentally played out all the variations, and there's really nothing left to the game. It's like tic-tac-toe to you or me after the first two moves.
Keats explained it this way: “Heard melodies are sweet, but those unheard are sweeter.” What's the point in playing out the dullest melody, when you've already heard the full symphony?
So, yes, most GM games end in resignation (those that are not drawn, that is).

GMs resign because they forgot how to do king and queen endings.
Hah.
In a blitz game the other day, I had a "K+R versus K" endgame, and my opponent didn't resign as I had only five seconds left on the clock. Problem is, I couldn't remember, within those five seconds, how to play this endgame, since I hadn't played it out in ages. Needless to say, I lost on time. ;D
You cannot lose if all your opponent has is a king.
In a blitz game the other day, I had a "K+R versus K" endgame, and my opponent didn't resign as I had only five seconds left on the clock. Problem is, I couldn't remember, within those five seconds, how to play this endgame, since I hadn't played it out in ages. Needless to say, I lost on time. ;D
You cannot lose if all your opponent has is a king.
My timer ran out and the game resulted in a draw then.

I always am tempted to resign as a matter of fashion (or is it not looking like an idiot who didn't see his blunder!) when it simply looks like things will collapse tactically, but the other side of me wants my opponent to fully prove that. This wouldn't come to playing till mate, but it would come to maybe my opponent tactically coming out a piece ahead with a winning endgame.
But for me there have been enough times where making them play out the variations work where it was totally worth being desperate. One time I played ...Bd4+??, believe it or not it was totally hanging to a rook on d1, but my opponent simply missed it as well incredibly, playing the routine Kh1 like in similar situations. In fact I was debating whether to resign or look like I didn't know my bishop was hanging till he took it by waiting, and perhaps playing on a few more moves. I went on to win that game.
Now I know GM's are GM's, but can you really be so 100% certain that just for that reason they automatically know they're going to win a piece in 4 or 5 sharp moves? It may be likely, but can you be so certain beyond doubt to the point where you just resign? They have missed mate in 1's before! In fact I haven't seen many GM games where that happens. Usually the resignation occurs after the smoke clears or where it's just about to clear in like 2-3 forced moves.

I always am tempted to resign as a matter of fashion (or is it not looking like an idiot who didn't see his blunder!) when it simply looks like things will collapse tactically, but the other side of me wants my opponent to fully prove that. This wouldn't come to playing till mate, but it would come to maybe my opponent tactically coming out a piece ahead with a winning endgame.
But for me there have been enough times where making them play out the variations work where it was totally worth being desperate. One time I played ...Bd4+??, believe it or not it was totally hanging to a rook on d1, but my opponent simply missed it as well incredibly, playing the routine Kh1 like in similar situations. In fact I was debating whether to resign or look like I didn't know my bishop was hanging till he took it by waiting, and perhaps playing on a few more moves. I went on to win that game.
Now I know GM's are GM's, but can you really be so 100% certain that just for that reason they automatically know they're going to win a piece in 4 or 5 sharp moves? It may be likely, but can you be so certain beyond doubt to the point where you just resign? They have missed mate in 1's before! In fact I haven't seen many GM games where that happens. Usually the resignation occurs after the smoke clears or where it's just about to clear in like 2-3 forced moves.
I gather that you havent played many GMs face to face....
GM draw alot of games. Sometimes this is because they have come to a known postion and the endgame is a draw. Sometimes this is meta-gaming; for example, half a point is enough to put then in a good position in a tournament, or the position is complex and "drawish" and they would rather take the half point than beat their heads against an uncertain game which will likely draw anyway.
Low level players, like myself, probably should not offer a draw unless it truely is a draw, i.e. about to get a third reptition of a postion, etc. Fight it out, mistakes happen down here is the trenches. If you make the other guy earn it he might blunder, run out of time, etc.