No blood has been spilled yet, but Grischuk only just barely survived against Aronian, and almost surely shouldn't have. Grischuk played a Gruenfeld sideline that doesn't have a particularly good reputation, as Black gives up a pawn not so much for play but to achieve a position with good chances to hold. He held, but only after a great deal of suffering and some help from his opponent.
On the other end of spectrum, Rajdabov got nothing against Kramnik's Lasker Defense, and they drew quickly.
Mamedyarov - Gelfand was a surprising game. Gelfand brought the Najdorf out of his dusty attic, only to have Mamedyarov choose the positional line 6.Be3 e5 7.Nf3 against it. Gelfand found an original way to handle it, giving up the d5 square to "Sveshnikov" the middlegame and then sacrificing the d-pawn in hopes of reaching a drawable ending. I'm not sure he'll want to repeat this line, but he did get the desired draw.
Kamsky - Topalov was also very interesting. Kamsky found an original move and idea as early as move 7 against the Najdorf: 6.a4 Nc6 7.a5!? Topalov declined the offer and a complicated middlegame ensued. Topalov found an interesting plan culminating in 15...c4, as a result of which both sides wound up with +2 pawn majorities on opposite sides: Kamsky on the queenside, Topalov on the kingside. Kamsky's was potentially more dangerous in the near term, so Topalov sacrificed the exchange for a pawn to neutralize it, and by the end it was Kamsky who was probably happier to split the point than his opponent.
Tomorrow they do it again with colors reversed, and I'll have the games, with annotations, some time later this afternoon or evening. Stay tuned!