Man so much FUD in this thread ^_^. No the AMD system won't be much (if any) slower in real world use. And yes, Intel does keep changing sockets, but in reality psh it's not a big deal--the "oh no, new socket every year" thing is FUD...how long has 1366 lasted and been top of the line? More than a year?

A nice socket 775 system is still excellent (e8400, anyone?). That socket has been around forever. Buy based on what you can get a killer deal on now, not based on what might be.
Anyway, if you want AMD then buy AMD...there's no harm in doing so. It doesn't perform much if any differently in real world use anyway. If you had a 4ghz amd 6-core and a 4ghz i5 750, for example...the i5 would be faster in most things that weren't heavily multithreaded, and the amd would win at heavily multithreaded things. But here's the thing...it's not enough slower or faster that you'd notice much difference. Especially in games.
I had a 4ghz 1090t (my friend wanted it bad so I sold to him because another friend sold me an i7 870 for $100, couldn't pass that up!)...my i7 870 at 4.2ghz is *slightly* faster in some things, but I feel that the AMD system was slightly faster at some photo related things that I do. Meh.
I do strongly feel that if you go AMD, spend the money and get the hex-core. They made some process tweaks and they run cooler, clock higher, etc. They make a better "quad core" than the actual quad core chips do. And there's deals to be had. If you go Intel, then great, get a 530, 750, 875k, or 920...the rest are just fluff imho (most of the AMD line is fluff too imho when you take OC'ing into account!)