Well, before recon-uk gets here and convinces you to buy a GT 480 for $220 (which is an amazing deal, by the way), I'll go ahead and plug my favorite deal:
The Sapphire 6950 2GB is on sale for $200 on newegg right now, and it's a great deal. Similar price-performance ratio as the GTX 480. I ordered one myself to crossfire with my current 6950, and I can't wait for it to get here.http://www.newegg.com/Product/Product.aspx?Item=N82E16814102987
It was originally set to compete with the 560Ti, and it trades blows with it on most every game. The extra memeory vs. the 560Ti could help in some games, and would help with AA enabled and such.