I think that is quite a good build.
750W would be overkill for a system with a single 6950/6970. However it is a solid choice if you want to be able to add a second 6950 in the future.
I think an easy way to cut $15 off the price of the build is to look for combos, such as this:
Corsair 750TXV2 $105
Corsair Vengeance LP 8GB (2x4GB) DDR3 1600MHz CAS9 1.5V CML8GX3M2A1600C9B $50
Combined price: $140http://www.newegg.com/Product/ComboDealDetails.aspx?ItemList=Combo.826118