Honestly, I think the 6950 is an excellent card, but $30 extra bucks for more memory that won't really get utilized isn't worth it to me. I think I'm just going to get the 560 Ti. After discount and rebates it's only $222 which is a great price.
UPDATE: just checked and it's a $20 discount instead of 10, so that makes total price only $212! :O Definitely getting it now!