1.d4 2...Yawn

Should that be 1... c5?! or 1... c5!?

Just curious. Obviously, it doesn't affect my level of play, but I'd love to know anyway!

That strikes me as an antithesis, Rich. 

There are like a billion gambits that have been thrown against 1. d4. People gambit against 1. d4 more than 1. e4 (I think) mainly because the game is slower and you can exploit the added tempo boost to counterattack and win the pawn back with better position than a classical defense.

The 1. e4 positions are much sharper, and the Black gambits produce razor-sharp positions.

Budapest Game; Eglund Gambit (the most obvious choice 1. d4 e5!); Old Benoni (1. d4 c5 also very duh after you see it)/Modern Benoni/Czech Benoni; Benko Gambit; Albin-Counter Gambit are the ones I can think of off the top of my head.

Benoni doesn't count! that makes budapest, albin,  englund, (which isn't taken seriously) and benko. Not too many.

baltic defense!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

BUDAPEST, BABY!

The Chigorin Defense is fairly sharp... 1.d4 d5 2.c4 Nc6.

Nimzo Indian is good if you like unblanced positions

This gambit -- the Englund Gambit -- is terrible. I speak from experience. I played in a tournament here on chess.com, The Englund Gambit Open, exactly to learn about the gambit.

http://www.chess.com/tournament/englund-gambit---open

I won the tournament, and I still say the Englund is terrible. Why? Well, what typically happened in this tournament is that with white you would play for the win (why not, right? your opponent just gave you a free pawn) and as black you'd try to somehow salvage a draw. Well it didn't really work too well. The most typical result was white winning. We even had a round where nobody was eliminated because everybody tied.

Don't waste your time learning it. It's no good.

I personally think 1.e4 is the boring opening, but only because I receive Exchange French and Exchange Caro treatment as Black.

People are less willing to play the Exchange Slav against 1.d4, for some reason.

Nothing wrong with the Exchange Caro. I face it all the time.

baltic defense man 1 d4 d5 2. c4 be5!!!!!!!!!!!!!!

1.d4 d5 2.c4 Nc6 3.Nf3

I think d4 is considered boring from the strict 1 e4 players' black point of view. Sometimes it's hard to counterattack without giving white a positional gain in return. Meanwhile white can play c4 and pressure the center and choose to play for e4 or finachetto the bishop and pressure the queenside. If black tries nimzo indian he usually has to give up a bishop for knight and in the classical nimzo white can treat it like a QG where he has the two bishops making Bg5 stronger. He just has to accept some awkward things like the queen on c3 but I still prefer that to the regular QG as white. Black can play the dutch, but he has to weaken his kingside and some other squares depending on what variation. In the KID black has to concede space. In the Benoni a completely mobile white center and a d6 weakness. These openings (maybe not the benoni) are fine and I love the KID but these attempts at counterattack probably lead to a small edge for white besisdes the nimzo.  This is all probably more annoying for them to play with than the sicilian.

On the other hand, in a must win situation, I might throw in 1 e4 because it is more likely to win or lose than draw, but I still think d4 gives white winning chances.