Well, noticing that your monitor is not 2560 x 600 (1920 x 1080), I'd steer away from the $280 ATI card as it gets outperformed by the $220 560 Ti (900 MHz) ...especially since that 6950 is not a "reference" card and therefore can't be flashed. The $60 could be put towards a better MoBo which would allow a future or even up front upgrade to twin GFX cards.
I don't see you benefiting from anything that Z68 offers, see what I mean here:
http://www.ukgamingcomputers.co.uk/difference-between-h...
This combo at $375 would cost just $25 more than what you listed and be capable of the GFX card upgrade.....so ya still ahead $35.
http://www.newegg.com/Product/ComboDealDetails.aspx?Ite...
For RAM I'd get one of these for $53 .... savings now totals $32
http://www.newegg.com/Product/Product.aspx?Item=N82E168...
http://www.newegg.com/Product/Product.aspx?Item=N82E168...
$80 a bit much for the HD ....savings now up to $52
http://www.newegg.com/Product/Product.aspx?Item=N82E168...
As for the SSD, you decide ..... all I can tell ya is what I sen on the test bench:
Boot to Windoze w/ Vertex 3 SSD - 15.6 seconds
Boot to Windoze w/ Seagate XT - 21.2 seconds
Load MMO took 45 seconds average on both SSD and HD.....HD won 3 outta 5 tests by tenths of a second but difference was so small as to be statistically insignificant.
As for the PSU, the XFX Core Edition 750 is an easy choice over the 650 watt Corsair. The 100 extra watts allows the addition of a 2nd GFX card and they both get identical 9.5 performance ratings from jonnyguru.
At $220 for the SSD it's an even tossup between that SSD and a 2nd GFX card. On one hand, the 2nd GFX card will have the biggest impact on gaming but installing the SSD later means some reinstalling / reconfiguration. Given the time of year, I'd suggest getting the SSD now and add the 2nd card as an XMas present to myself (unless ya can get someone else to spring for it). Here's what the 2nd card will do (source Guru3D):
-------------560 Ti-CU 560 Cu SLI 6950 6950 X-fire
COD-MW 134 218 127 150
Bad Company2 51 98 50 96
Dirt 2 72 134 72 131
Far Cry 2 88 153 76 147
Metro 2033 26 49 25 50
Dawn of Discovery 73 123 78 90
Crysis Warhead 51 87 51 87
Total 495 862 479 751
The formatting stinks but ya can see that the 2nd 560 takes you from 495 to 862 total fps ..... the 2nd 6950 from 479 to 751 fps.