Another vote for the 7950 here
Since the recent price drops it has become a choice hard to ignore!
There have also Just this last week been more price drops which I am not sure have filtered down through to the suppliers...?
This card easily beats out the 660Ti.
The 670 carries an average of a 12% lead across most benchmarks over the 7950 but is a pretty over priced card - at the 670 price point you can start being able to buy the cheaper versions of the 7970 which is a card that can make the 680 look weak ^^
AMD's latest drivers are also looking great - The most recent driver (not sure it has a public release yet) brings a card like the 7950 an extra 5 - 6 fps in BattleField 3 for example
With their current pricing structure & driver progress AMD is on a roll
Oh - I just bought the Asus Direct CU II TOP 7950 yesterday (new for $306 off ebay) after having my head buried in reviews this last week ~_^