If gaming is the biggest usage, the Sandy Bridge is very attractive .... tho less so the higher the amount of money you spend on twin GFX cards. The x8 x 8 limitation is non existent at say the 470 GTX / 68xx level but can get noticeable from there on up. If you running any intensive programs which benefit from the extra bandwidth of 1366, I'd suggest otherwise.
I only would use AMD CPU's in a < $1k build.
Well I will be using the pc mainly for gaming and autocad+photoshop.