Looks like a good bundle for the motherboard/processor.
Pick up 8GB of 1600Mhz DDR3 RAM.
Something like this would work.
Instead of the GTX660 that you posted, may I point you towards the
Powercolor Radeon PCS+ HD7870 Tahiti LE for $249.99, $219.99 after rebates.
Instead of being a regular 7870, it's actually a 7950 with a quarter of the GCN modules disabled, and 2GB of memory instead of 3GB. Either way, it will be quite a bit faster than a GTX660, and you'll get two free AAA titles: Bioshock Infinite and Tomb Raider.