You said it all sounds well thought out and yes of course that would generate a great deal of interest, i love the idea if you do a poll to take the idea to chess.com staff count me in ! 
Make Chess interesting for spectators? Join games in progress
And/or you could have it like vote chess - debate the next move, and have the chess.com community argue their points for the next move and see if they are right.
You could always just play against your computer
Well, yes, but it wouldn't be as much fun for me. For me, I like live, OTB chess best. After that, there's online chess against another person. After that, computer chess, but it's a long way down.
My proposal combines the style of live online chess with an element of spectator participation.
Another thread got me thinking. Sure, we like Chess, but it doesn't get much in the way of coverage in the media, and it isn't hard to see why. Let's be real. Darned near everyone thinks it's dull to watch. I've read lots of ideas of how to make it interesting, but either they don't really address the problem, or they are tongue in cheek suggestions that either involve blood sports or, more likely, girls in bikinis.
Then a thought hit me. It won't make non Chess players like watching Chess any more, but for the small fraction of us who actually play and might take some small interest in who wins a major tournament, I thought of a way to make things at least somewhat interesting.
I want a way to play along. When I am watching a Chess game, what I am really doing is looking at the board and thinking, "What would I do?"
So, here's how I think it could work. I'll describe it in terms of chess.com, but it wouldn't have to be done here. It's just how we are familiar with things. During a major tournament, like a world championship or something, Chess.com covers it live. By "covers", what I mean is displays the current state of the game. When a move is made, a board updates. Now, imagine that the spectators could, at any time, issue a challenge from the current state of the board as a starting position, just as if they were starting a live Chess game.
In other words, while Shirov and Anand are playing (they happen to be mentioned on the Chess.com front page today) we follow the game live, and of course the moves come slowly, with several minutes between each move except for a few quick flurries. While pondering the move, I become convinced that the right thing to do is move Ba6! I go into a live Chess setup screen, saying I want to play black in a five minute blitz game. If there are any takers, I play the move I want to, and we play out the game in rapid fashion. By the time it's done, maybe the GMs have made another move, and we can do it all again.
It's a way of participating more actively in the play of the game.
What do you think? Is that, or something like it, a way to generate interest? Or is there some other way? (Other than the bikinis, that is.)