You don't need SLI/CF for those games. CoDBO is not as power-hungry as Crysis. Even a gtx 460 will play smoothly at your resolution with image quality maxed out. I suggest you wait for Tue for gtx 560 to be released for about $270 US. WoW is a very dated game which can be played on even modern onboard video. It is, however, very network latency-dependent. So I'd focus on getting fiber or the fastest DSL if I'm serious about WoW grinding.
Not sure why you're limiting your hardware selection to one store. Probably has to do with your payment. I get whatever I can fastest & at a reasonable price.
No to i7 950. Why get last gen when you can get current gen like LGA1155? There's one socket coming out to replace LGA1136. At least i5 2500 + a P67 ATX mobo. Throw in a 500-600W quality psu like Seasonic. Any mid or full tower case. RAM will be DDR3 2x2GB. Any speed. Remember to focus on gpu if given the choice since you're building a GAMING rig. i.e. a more expensive gpu & a cheaper cpu. If you plan on keeping the gpu for a long while, get a slightly overkill one like GTX 570. But I'd still wait for the 25th.