I set out with the same budget as you but ended up saving a boat load of money
Here is my final build:
Case: Antec 900 II - $119.95
Decent wire management, comes with a bunch of fans and filters as well as fan controllers, its very very heavy duty aluminum and steel, its not a full size tower but has the width and depth to house an army. I call it C3PO
Power Suppy: Corsair 850TX - $159.99 USD
It is not modular so if you wanted to go modular you could spend a hundred dollars or more and go modular. This thing is the most stable PSU I have ever seen.
Mobo: ASUS890GX - $139.99 USD
ASUS M4A89GTD PRO/USB3 AM3 AMD 890GX SATA 6Gb/s USB 3.0 HDMI ATX AMD Motherboard. Why? I am using the on board 4290 as a dedicated physx processor whilst running 2 Crossfire 5850's, now the this board only allows for 8x on two PCI slots but frankly who the hell is going to see a difference. If you wanted to upgrade a bit then go with a board that supports two or four x16 slots. I find it totally unecessary with 2 cards crossfire and a dedicated physx chip. AM3 Socket. This board has a bunch of cool features, memory oc'er, turbo buttons and its covered with heatsinks and feels pretty darn sturdy.
CPU: Thuban 1090t $295.99
This is the first CPU where I just tried EVERYTHING and for the most part it worked.
Overvolting, undervolting, overclocking screwed with pretty much everything I could and then in the end just left it at 3.78 without Core Power Boost and it runs 23c with my air cooling, gets up to 35c under crazy load (which is very hard to do)
I went a bit crazy in the beginning took this thing to 4.4 and it ran stable but warmer than I wanted it too with air cooling. Its a dandy of a chip.
RAM: Kingston HyperX DDR3 1600 (7 CAS) $141 per 4 gigs, I have 8 gigs and use about 1-2 gigs with all my apps running and 2 / 3 instances of WoW / Aion running.
I went with this RAM because a buddy of mine OC'd this to 2200 and swears by it.
GPU: You have money to burn with this build so Crossfire two 5970's and tell us all about it
I looked at the 5870 and could not justify the jump in price for the performance / increase in specs in comparison to the 5850 hence me getting two 5850's.
Storage: Boot / Gaming go with the 10,000 RPM Sata Six WD Velociraptor 64mb cache, don't fall for the Solid State trend yet, let the price come down and the technology fall in line before you get a SSD.
I think you could probably chose the rest for yourself.
Ok now on topic. I wouldn't get a velociraptor. If you want speed get an ssd if you want size get an HDD. If you want both get both. If you want both in one partition get a good hdd, a good small ssd and HDD boost. If you want both in one drive get a momentus XT.
That may have been confusing so lets sum it form fastest to slowest
1: SSD with all apps and HDD for storage(expensive and SSD is small)
2: smaller SSD with HDD boost and a fast HDD(almost as fast as an SSD, reasonably priced and very large)
3: momentus XT(reasonable speed, cheap and relatively large)
4: HDD even a fast one like a velociraptor(slow, expensive, Quiet reasonably large)
as for the cpu I'd get a 930
as for the gpu I'd get fermi especially for your usage(maybe 480sli or 470sli)