If you get an AM3/AM3+ compatible mother board, i would suggest going the Athlon route, so that you may upgrade to piledriver in the next year or two. For some reason I keep ragging on the trinity set-ups here in the forums... but the reason is that it simply doesn't make sense for a system dedicated to gaming. A HTPC to run bluray and MythTV and some light gaming? WONDERFUL! But if you're looking to play some serious games I would go the Athlong route with the better videocard. -OR- you could always go the Pentium G series route... good performers and can be had for less than the Athlon, with the option to upgrade to i5/i7
Yeah, this is a good build. Maybe keep an eye out for a cheap GTX 460 1gb. You can sometimes find them in the 100 dollar range... but then again there's no real performance difference between it and the 7770...