USAGE FROM MOST TO LEAST IMPORTANT: Games, video streaming, web browsing. Most demanding games i'll be playing is Skyrim ,Tera Online, Guild Wars 2 ,Diablo 3.
CURRENT GPU AND POWER SUPPLY: At the moment nothing I am selling my current rig and building a new one this week.
OTHER RELEVANT SYSTEM SPECS: i5-2400, Asrock extreme3 gen3, 8GB G skill 1333Mhz RAM, and getting either an OCZ ZT full modular 550w or a CORSAIR Builder Series CX600 V2 600W. Leaning more towards the OCZ for full modular and therefore lesser system heat.
PREFERRED WEBSITE(S) FOR PARTS: Newegg, Amazon, Ncix, Microcenter, Tigerdirect. Wherever has the better deal
COUNTRY OF ORIGIN: U.S
PARTS PREFERENCES: I don't care if it's AMD or Nvidia, just something that will play my games at high setting at the magic 60+ FPS. I do prefer the Frozr or Asus DCUII series cards though.
OVERCLOCKING: I'll probably overclock the card a little bit
The 7870 is your best bet. Excellent value atm. It performs better than the 448 core even though it's cheaper.
It still won't give you 60fps on skyrim at max settings. It should on high though.
edit: sigh, you read the latest article on tom's i take it? Please read the conclusion. The problem will be patched soon and there is a fix already. It's also tiny. You would never notice without comparing blown up screens shots for hours.
The 7850 also uses a lot less power than any of those cards (except for the 6870, the 7850 only uses somewhat less than the 6870, but it is in a whole other performance tier), so it will save you money over time.
Oh, and that 6870 you are looking at is way overpriced unless it's a 2GB model and even then, that 2GB only matters for CF where it has the GPU performance to use resolutions/quality settings/AA to the point where 1GB is not enough.
A 6870 1GB should cost between $150 and $175. Going beyond that is treading into GTX 560 TI 1GB and Radeon 6950 1GB territory.
Forget all the cards you've mentioned since Newegg got back in stock the Sapphire 6950 2GB for $249.99. May be you can even flash it to 6970. Either way, it's a steal.
Like aicom said, the 7850 is faster than the 6950. Also, newer 6950s can't be flashed because instead of just disabling the cores in the BIOS, AMD also damaged them with a laser (no joke, look it up) to stop the flashing to get a 6970 at a 6950 2GB price.