First, if you're sure about not wanting to CF, switch the board to a Gigabyte GA-P55A-UD3. It should save you a good $60 (US), but it only has 1 PCIe 2.0 slot.
Second, similar to the first note, you can downgrade to a 550W if you're sure you don't want Crossfire. If you want the option, I would step up to a 750W if you want more room to expand. It's not necessary though.
Third, you should look into finding some 1333 mhz CAS Latency 7 (timings 7-7-7-x) sticks of RAM. 1600 mhz is only used when overclocking, and CL 9 isn't very good.
Fourth, WD is losing the HDD battle right now. Pick up a Samsung Spinpoint F3 1 TB (or two of them). If you can't find it, get a Seagate 7200.12 1 TB. These will both be a lot faster, quieter and cooler than the WD.