I'd agree about getting an i7 setup, it won't actually cost much more as you could probably save a bit on the GPU.
3x1GB DDR3 1333
You can get a GTX 260 for cheaper than $300, but since that motherboard supports CF, I'd recommend going with a HD 4870
, it's pretty much identical in performance to the GTX 260.
If you're not overclocking, don't bother with an aftermarket cooler, stock cooling will be fine and you can save some money.
You can save some money on the PSU as well, this
will be more than sufficient for that build.