Gee, I'm already regretting creating this thread, why create a thread about it when I could just google and research it on my own? Anyhow, I might learn something in this thread that I won't on wikipedia.
1.d4 d5 (2.Nf3 Nf6 3.e3) 2. e3

I usually castle early, develop my pieces, then play ...c5 late to open up the position. Here is an example game I played here.
It usually happens to me with the knights out first, but it pretty much allways transposes into the same line. I'm assuming white most likely wants to head into a colle opening, and I really haven't gotten a clue on my ideas here. I understand that white wants to push e3 and get a crude kingside attack going usually, but what is black to do?
I usually counter this with an early c5 myself, trying to take the iniatiative but it usually goes ape. I had a (rapid) game in this variation just recently where I got crushed after some early misstakes and not getting the pawn back after he snatched it and tried to hold into it. I'm starting to doubt my early c5 here, what is the usuall line for black? What is the equalising line for black which I'm sure exists in the colle.