Main line 1. b4 e5. 2 Bb2 Bxb4 3 Bxe5 Nf6

I don't know the name of this main line, but it's one of the mainlines. Here I post my answers of this opening.

Mostly I play e3, to have the posibility to develop my Bishop. But when I explore my book, it's 4. c4 what the best move is. Now Black isn't able to play 4. ... d5, otherwise Black doesn't have centerpawns.

When white plays c4 before Black can play d5, Black hasn't have any pressure on the d2 pawn. I have posted a topic about a game earlier today, but at analyzing the game and learning from the book, I discovered, that 4. c4 is the best move. You mustn't allow Black playing the move to d5.

But in most games, Black will play d5 to open the field. What do you have to do then?

Okay, this is what Yury Lapshun says in his book Play 1. b4! Now I must remember these moves, when I face this opening again. At the moment, October 4 2010, I've played 4. c4 only two times, but it will be more from now on. Later, I will come back to this topic and will share my experience with that answer to you all. See you later.

very interesting idea with c4 move. Thanks.

is it posible to play Sokolsky opening and to make c4 move?.. 

Yes, 1 b4, e5, 2 Bb2 d6 3 c4

it's a main line.

Hey, guys! I've posted some additional stuff on the Exchange Polish. If you want to pick up some more theory on this variation - you can check it in my blog: http://www.chess.com/blog/Eugen/sokolskypolish-opening-1b4---the-exchange-variation

Yes, in the main line 1.b4 e5 2. Bb2 Bxb4 3.Bxe5 Nf6 4.c4! is the most accurate move. Because it stops d5.

But black often plays d5, see above. Because it opens the possibility for attacking on Kingside.