Hey guys, I went with the SAPPHIRE Radeon HD 7750, and it was piece of cake installing it (had to rip out some random flimsy metal junk by the slot, but that was no big deal). It fits perfectly, and it is a pretty sweet card. Best I've ever had, as I tend not to splurge on components, and I also have a company to run from the same comp, so a really sweet graphics card would be rather distracting.
I tested an old WOW account, and maxed out the settings and got 60fps...better than the 24 I was getting on "Good" settings.
For those of you not using Dropbox, I want to score some free space. It is an awesome program, and great with an iPhone. Shameless plug, I know, but I love free storage space;) http://db.tt/dlyr8Ke