1. Why a full tower case? Go with one of the mid-sized towers that were recommended in your other thread. Even if you need room for expansion, with what you have now, a full tower case is a waste of money. You could easily save yourself $100 or more on the case alone if you pay attention to your earlier posts.
2. Why do you need a 750W PSU for that rig? I think you've overshooting by 100-200 watts. At the most I'd have grabbed the 650W -- specifically, for a little more buck, you get a LOT more bang with the SeaSonic X650. It is modular and gold-certified, which will save you a lot of grief.
3. You have quite a bit of RAM for that rig. Unless you intend to do more than game, you could probably do with 4-6GB rather than a whole 8GB. But that's personal opinion.
4. That 640GB is pitiful compared to a 7200RPM 1TB (or more) equivalent you could get if you shaved some watts of your power supply and got a less redonkulous case. Also, you mentioned Western Digital but the model series. Caviar Black? Blue? Green? I'm assuming it's a Black. Whereas the 640GB WD Caviar Black is about $70, the 1TB drive is nearly twice the space for only
Interestingly enough; you could get a 1TB drive for $100, or two Samsung SpinPoint F3 500GBs for $100 shipped for the handiness of two drives in one (or RAID-0, if that's your schtick).
5. Why did you get a motherboard specifically designed for core tinkering (i.e. unlocking and multiplying) and then pick up a quad core? It's not a bad CPU -- I'm a huge fan of that specific chipset, in fact -- but I am just not seeing the correlation here. The motherboard you chose is nice - but again, by optimizing your build and saving cash off shaving down the GPU, tower, PSU and RAM, you could get the Asus AMD 890FX for $50 more and STILL have enough left over to get a far superior power supply, higher-quality RAM, and a less overkill video card.
6. 2GB on the 6950 is way too much, I'd think, but if you are ordering NOW it's only a $20 difference. Still I probably would get the XFX 6950 1GB and spend that $20 towards a HDD that has a better capacity. You would save even more if you got the Sapphire 6950 1GB