They really arent much better than the 6700's, don't know why the price is so high. You'll get better performance for the same price with an EVGA 560 superclock. http://www.newegg.com/Product/Product.aspx?Item=N82E16814130743
Those are excellent bargains at the moment, about 3 months ago they were near 200 dollars. 130$ now, same as the 7770.
If you cant buy from newegg and you're looking at a place that will ship to you, make sure you look for the EVGA superclocked 560. If you try and get a 560ti the price will jump up, it's a different card.