The round started with a 7-way tie for first, and now it's down to two. Gata Kamsky wiped out Larry Christiansen with a crushing attack, while Alexander Onischuk defeated Varuzhan Akobian in what looked to me like the latter's overreaction to the possibility of playing a bishop vs. knight ending. In the latter game, Akobian could have played 31...e3, and after 32.fxe3 Qxe3+ 33.Qxe3 Nxe3 entered an ending that has to be at least slightly in White's favor, but avoiding this with 31...h4 left him a pawn down for nothing after 32.Qxa5. (Maybe he missed 32...e3 33.Qe1(!)?) Onischuk had no trouble converting his material advantage, and so he and Kamsky share the lead with 4 out of 5.
In the other games featuring players who started the day tied for first, Shulman - Nakamura was a good battle in a Blumenfeld Gambit. Black might have had some advantage after the pedestrian 21...Rf7, but Nakamura's 21...Qg6 lead to a long and attractive sequence of captures resulting in Black's having the exchange for two pawns. Unfortunately for Nakamura, White's position was easier to play and Shulman might have pressed harder than he did. (One possible way he could have improved was to send the a-pawn on its way early on, trying to stretch Black's defenses too thin.)
And then there's Stripunsky-Yermolinsky, which I simply don't understand. White went for a kingside attack while Black played on the queenside, and in the final position (or at least what I have as the final position) White's attack is dead. In fact, White's dead, period: Black can play 33...Rc2, when (for example) 34.Qb1 Qd6+ 35.Kh1 Qxd3 is utterly hopeless for White. This I understand; what I don't understand is why rather than 33...Rc2 it says "draw" in the game score.
Moving down the scoretable, in Ehlvest - Kraai White blundered a pawn; Black converted and won. Krush - Hess saw Krush get some good luck when Hess blundered in an only slightly tricky position. 33...Qxf4 was slightly better for him (34.Rxf6 e3 35.Rg6 e2); instead, he uncorked 33...Qxf5?(?) and resigned after 34.Nd5 Qe5 35.Nxf6.
In Benjamin - Lenderman tried a little-known move, 12.Re1, in a variation that was very dangerous for a time until it was solved in the mid-80s. For players around Benjamin's age, this variation is well-known, for Lenderman, it might as well be the Double Muzio. To me (being in the right age group to remember the battles in this line), 14...Bg4 is just obvious - it's the reason 12.h3 is the main move. Failing to play this, White got the sort of position that made this variation the fearsome weapon it was for a few years, and Benjamin won pretty easily.
Khachiyan - Shabalov was a horror show. White was better - often winning - for a long time, including in the rook and bishop (with two pawns' compensation) vs. two rook ending. White never figured out how to finish the job though, and by move 58 (a few moves sooner, actually) he should have given up and gone for the draw. Instead, trying too hard to avoid a draw, he succeeded: 58.d7?? Rc3+ 59.Kg4 f5+ 60.Kh5 and White resigned before getting mated by 60...Rh3+ 61.Kg5 Rg2+ 62.Kf4 Rg4#.
In Kudrin - Kaidanov, White had been losing ground, but 36.Rd1?? lost straightforwardly to 36...Nd4 and 37...Qh2.
Finegold - Altounian wasn't so much better for White until 27...Rb8. Finegold evaluated the variations better, and achieved a winning rook and knight vs. rook and bishop ending that Altounian quickly resigned.
Shankland - Robson was odd. White was winning until near the end, and even at the end 32.Ke3 rather than 32.Kc3 seemed to favor White. Instead, he repeated moves and they drew.
Finally, Black was better for much of Bhat-Gurevich, but White slipped out and escaped with a draw.
Standings After Round 5
1-2. Kamsky, Onischuk 4
3-6. Nakamura, Shulman, Stripunsky, Kraai 3.5
7-10. Akobian, Christiansen, Yermolinsky, Krush 3
11-14. Shabalov, Kaidanov, Benjamin, Finegold 2.5
15-17. Ehlvest, Hess, Robson 2
18-23. Lenderman, Kudrin, Bhat, Khachiyan, Shankland, Altounian 1.5
24. Gurevich 1
Tournament site here.