From here, White can try a few different moves, but each one has a drawback.
a) 3.g3 -- here, I think that Black's most accurate move is 3..c6! Now 4.d4 ed 5.Qxd4 d5 has been tried in many games and seems fine for Black (Kosten's excellent book on the English recommends delaying Nc3 in part because of this line). If White tries 4.Nf3, then Black can play 4..e4 5.Nd4 d5 6.cd Qb6!?
This is never played with colors reversed (1.e4 c5 2.c3 Nf6 3.e5 Nd5 4.Nf3 Nc6 5.d4 cd 6.Qb3), presumably because ..e6 would be a good response. From the diagram, if White plays 7.e3, it is clear that the extra move g3 is actually detrimental. If instead 7.Nb3, then Black can gain the initiative with 7..a5!, threatening to trap the knight. This was recently played by Bacrot, and looks pretty strong. Therefore, instead of 3.g3, most people play 3.Nf3 Nc6, with another split:
a) 4.g3 Bb4 (4..d5 is also surprisingly hard to get an advantage against). White would love to play 5.Nd5, but Black responds with 5..e4, and the extra move Nf3 is suddenly a drawback. So most games continue with 5.Bg2 0-0, reaching a well-known position. I can't begin to do this line justice in the space I have here, but it does score well for black and I'm not particularly inclined to play it as White.
b) 4.e3 Bb4 5.Qc2 Bxc3!? 6.Qxc3 Qe7!.
I'm astounded at how annoying this move is -- my computer actually thinks that Black has a slight advantage here, and while I'm not sure about that, I think it is fair to see that equality has been achieved. Basically, Black will play ..d5, White's queen will get kicked around, and Black's lead in space and development will be enough to counter the bishop pair. So why can't White players try the same thing in reverse, as an anti-Taimanov line? Essentially, because the Black knight is still on g8, and thus 1.e4 c5 2.Nf3 e6 3.Nc3 Nc6 4.Bb5 can be met with either 4..Nge7 or the immediate 4..Nd4. If an enterprising White player tries to waste a tempo with something like 4.a3, then Black can simply respond with 4..a6, which is part of his plan in the Taimanov anyway. Speaking of a-pawn pushes:
c) 4.a3 d5 (4..g6 is also playable and roughly equal, because the a3 move becomes useless) 5.cd Nxd5, and we reach our final split:
i) 6.Qc2 Nxc3!? 7.bc Bd6 8.g3 Qe7(!) 9.d3 b6 has done pretty well for Black. White probably wishes the a-pawn was back on a2.
ii) 6.e3 Nxc3 7.bc Bd6 is similar. I always enjoyed playing White in these positions with colors reversed, and I would rather play Black here, although it's a matter of taste.
iii) 6.e4 Nf4!? 7.d4 ed 8.Bxf4 dc
Now 9.Qxd8+ Nxd8 10.bc Ne6 is not what we want as White. With colors reversed, Black usually takes the pawn back immediately, but here, 9.bc gives Black the extra option of 9..Qxd1+, and all of a sudden recapturing with the rook leaves the a3 pawn en prise. Curse you, extra move! To be fair, White can recapture on c7, but the position isn't very inspiring.
So there you have it, a peripheral look at what everyone knows already: the reversed Sicilian seems fine for Black.
