I have enjoyed watching the excellent live coverage of the U.S. Championship, though I generally end up playing through the games at Chessgames.com (Men's and Women's). There have been a number of hard fought contests, including Kaidanov - Holt (utter insanity), Gareev - Christiansen, Robson - Bryant, Benjamin - Hess (a Capablanca-esque endgame performance), Hess - Finegold, Kamsky - Shabalov, and Baginskaite - Ni. I have also been amused by the trapped pieces in Sammour Hasbun - Kaidanov and Abrahamyan - Baginskaite. Of course, I have been following Yaacov Norowitz most closely, and while he was tortured by GM Larry Christiansen in the first round after an opening error, he bounced back to take control against GM Alex Stripunsky in the second and has a half point out of two, which is certainly not a bad start considering the caliber of competition he is up against. Christiansen is, in fact, tied for the lead with Gata Kamsky and both seem to be playing great chess. You can see my notes below, or download the PGN.