Anand has cleverly chosen the very solid (drawish) Lasker Variation of the Queen's Gambit Declined. Those of you who want to look up key games will want to have a look at the Karpov-Yusupov ("Jussupow" in ChessBase's databases) Candidates match in 1989, I think, and also some of Kramnik's games with Black in the 1990s.
It's a super-solid variation which gives Black almost no winning chances at all against a peer, but it's hard to beat too. For a single game, it's an excellent choice in a situation where a draw is a good result. Here are the moves so far:
1.d4 d5 2.c4 e6 3.Nf3 Nf6 4.Nc3 Be7 (No 4...c6, going for the Semi-Slav) 5.Bg5 h6 6.Bh4 0-0 7.e3 Ne4 (The Lasker Variation) 8.Bxe7 Qxe7 9.Rc1 c6 10.Be2 (Usual is 10.Bd3, but it will transpose back to normal lines momentarily) 10...Nxc3 11.Rxc3 dxc4 12.Bxc4 Nd7 13.0-0 b6 14.Bd3 c5 15.Be4 Rb8 16.Qc2 (16.Qa4 is the other main move) 16...Nf6 and we have the following position:
This last move is a little unusual, but not a novelty. It's quite logical, too. Black will accept a weakness on c5, but in return gets excellent play. For instance: 17.dxc6 Nxe4 18.Qxe4 bxc5 19.b3 Bb7 followed by 20...Bxf3, as played twice successfully (meaning with a draw) by Polish GM Miroslaw Grabarczyk.
8:50 Update
The first predicted moves were played: 17.dxc5 Nxe4 18.Qxe4 bxc5, but now 19.Qc2 as played in a correspondence game. So far they're following that game with 19...Bb7 20.Nd2 Rfd8 21.f3. White has the better structure, obviously, but Black's activity is very hard to restrain. Here's a sample variation: 21...Qd6 22.Nb3 Ba6 23.Rc1 (23.Rd1?? Qxd1+ 0-1 was the end of the correspondence game - a pen slip?) 23...Bd3 24.Qf2 c4 and White has nothing better than to liquidate to a draw: 25.Na5 Qa6 26.Naxc4 Bxc4 27.Rxc4 Qxa2 28.R4c2 with equality.
9:15 Update
Not much since the last update, but perhaps Anand is out of his preparation. Instead of 21...Qd6, Anand chose 21...Ba6, and now instead of the natural 22.Rc1 Topalov played 22.Rf2.
This overprotects b2, so now there's a threat against c5, but it weakens the d1 square. Anand might even be a tiny bit better by doubling on the d-file. If Anand does not succeed in getting this counterplay, however, he can wake up one moment with a strategically lost position. So we have prospects for a decisive result today!
9:30 Update: Some Variations
Anand played 22...Rd7, preparing to double on the d-file, and now we're waiting for Topalov's reply. It looks like Anand has the more comfortable, maybe even slightly better position. Black's c-pawn looks weak, but it's pretty resilient.
For starters, taking on c5 right away is nothing: 23.Rxc5 Rxb2! 24.Qxb2 Qxc5 and Black is a little better.
Trying to pile up with 23.Ne4? is an outright error, and demonstrates the weakness of White's back rank: 23...Rxb2!, with the point that 24.Qxb2? Rd1+ mates next move.
Piling up the other way with 23.Nb3 is no big deal either: 23...Rbd8 24.Rd2 c4 25.Nd4 Qh4 26.g3 Qg5 is also slightly better for Black.
White's best is probably the move Topalov just played: 23.g3. This takes care of the back rank worries and stops the sometimes annoying ...Qh4 from occurring. I'd expect 23...Rbd8 here, and after 24.Kg2 Black can choose between moves like 24...Bd3, 24...e5 and 24...h5.
9:50 Update
After 23.g3 Rbd8 24.Kg2 Bd3 Topalov chose 25.Qc1, which renews the threat to c5. So 25...Ba6 is possible, when 26.Qc2 Bd3 or 26.Ra3 Bd3 27.Rc3 Ba6 are an invitation to rapid games on Thursday. 26.Nb3 is more aggressive, when the obvious possibilities are:
(A) 26...c4 27.Nd2 (threatening the c-pawn) 27...Qg5 (counter-attacking against the e-pawn) 28.h4 (28.Nxc4 Rd1 29.Qc2 Bxc4 30.Rxc4 Qxe3=) when Black can choose between the dynamic 28...Qh5 followed by ...g5 and the counter-attacking 28...Qa5.
(B) 26...Rd1 27.Qc2 Qb7! 28.Rxc5 (28.Nxc5 Bf1+! 29.Rxf1 R8d2+ 30.Rf2 [30.Kh3?? Qd5-+] 30...Qd5 and White must give up his queen [e.g. 31.Qb3?? Rxf2+ 32.Kxf2 Qd2#], though he's not too much worse as a result.) Bf1+! 29.Rxf1 Rxf1 30.Kxf1 Qxf3+ 31.Ke1 Qxe3+ with a perpetual.
10:15 a.m. Update
As expected, Black retreated with 25...Ba6, but after 26.Ra3 he played the ambitious 26...Bb7. I didn't find anything great for White after 26...Bd3, but Anand preferred to put the bishop on the long diagonal. Now Topalov chose 27.Nb3 (27.e4 f5 gets crazy), and now Anand probably needs to put a rook on the c-file, which looks like a minor concession.
10:40 a.m. Update
The game remains very interesting, and could explode at any moment. Here are the latest moves:
27...Rc7 28.Na5 Ba8 29.Nc4 e5
Black's aim is clear: he wants to play ...e4 and to meet f4 with ...Rd3. White can stop this with 30.e4 though Black is absolutely fine after 30...f5 31.Nd2 fxe4 32.Nxe4 Bxe4 33.fxe4 Rd4.
Another White possibility is 30.Ra5, trying to aim at both Black weaknesses, and then we could have something like 30...e4 31.f4 Rd3 or - even better - 31...Bd5 hoping to follow with ...Be6-g4-f3+.
Sure enough, White has played the safer 30.e4 and Black replied 30...f5.
10:50 a.m. ET Update
Wow, Topalov has played 31.exf5 - this seems crazy! Anand immediately played 31...e4, and now the position looks extremely dangerous for White. This will almost definitely avoid the rapid play, but most likely not the way he wants.
10:52 a.m. ET Update
Unbelievable, Topalov is committing suicide here! He has just continued with the horrible 32.fxe4??, and after 32...Qxe4+ White's position is 100% lost. For instance: 33.Kh3 Rd4 (threatening 34...Qg4#) 34.Ne3 Qe8! 35.g4 h5! White's kingside is obliterated and his king likely to get mated. Topalov has absolutely lost his mind.
11:05 a.m. ET Update
Those moves have been played: 33.Kh3 Rd4 34.Ne3 Qe8 35.g4 h5 and now all that's left is for Topalov to find his last way to flail around.
This is just target practice. After a few desperate minutes Topalov played 36.Kh4, and now the most direct win is 36...Qd8+ 37.f6 hxg4, when a move like ...g3+ is in the air. But frankly one doesn't need to find anything too concrete - White's king is on h4, and Black has five attacking units going after it.
11:20 a.m. Update
Topalov is still battling. After 36.Kh4, Anand chose the sufficient and more human 36...g5+, getting the Rc7 into the action as soon as possible. Topalov played the forced 37.fxg6 Qxg6 38.Qf1, and now Anand's best is 38...Rxg4+ 39.Kh3 and now either 39...Re7 (threatening 40...Rxe3+ 41.Rxe3 Rh4+ 42.Kxh4 Qg4#) or the subtler 39...Rf7 (with the idea 40.Rxf7 Bg2+ 41.Nxg2 Rh4+ and 42...Qg4#).
It's not done yet, but it is winning, and he has 18 moves for the last three moves to make it to the time control.
11:50 a.m. Update
Still going! Anand did indeed play 38...Rxg4+ 39.Kh3 Re7, and Topalov dealt with the mate threat (40...Rxe3+, 41...Rh4+, 42...Qg4#) with 40.Rf8+ Kg7 41.Nf5+. This sets a small trap: 41...Kxf8?? 42.Nxe7+ Qf7 (42...Kxf7?? 43.Rxa7+ +-) 43.Ng6+! Rxg6 44.Qxf7+ Kxf7 45.Rxa7+ with a better position. Of course Anand didn't fall for it though: 41...Kh7 and now White must deal with the threats 42...Bg2# and 42...Rh4+ followed by 43...Qg4#.
So the only move is 42.Rg3, and the following forced moves have happened quickly: 42...Rxg3+ 43.hxg3 Qg4+ 44.Kh2 Re2+ 45.Kg1 Rg2+ 46.Qxg2 Bxg2 47.Kxg2 and although the material situation isn't that bad for White, it's bad enough after 47...Qe2+ and ...Qxb2. White's thoroughly lost.
12:00 p.m. ET Update
More moves and a diagram: 47...Qe2+ 48.Kh3 c4
White is in a sort of zugzwang here, and the ever-present threat to take on b2 doesn't make White's life easy either. It's a 100% win.
12:25 Update
We have a few more moves: 49.a4 a5 (Zugzwang.) 50.Rf6 Kg8! (50...Qxb2 won too - 51.Rh6+ Kg8 52.Rxh5 c3 53.Ne3 and now as long as Anand avoids 53...c2?? it's a win. But Anand's 50...Kg8 is even stronger, disrupting the coordination of White's pieces.) 51.Nh6+ Kg7 52.Rb6 Qe4 53.Kh2 Kh7 and now White's knight is just dead. Black will start cleaning up pawns at his leisure.
The game has been as good as over for a long time now, but resignation can't be far away.
12:28 - A Note on the Pawn Ending
Some commenters thought that 47.Rf7+ led to a drawn king and pawn ending. They're right that it leads to a king and pawn ending, but it's not the least bit drawn. After 47...Kg6 48.Rg7+ Kf5 49.Rxg4 hxg4 50.Kxg2 Ke4 51.Kf2 Kd3 the win is trivial - a 1500 should beat Topalov here.
12:35: Anand Wins: Game Over, Match Over
Here are the remaining moves: 54.Rd6 Qe5 55.Nf7 Qxb2+ 56.Kh3 Qg7 0-1
The final position:
Congratulations to Viswanathan Anand, who continues his reign as world champion! (Stay tuned later for the full annotations.)