I recently got a new laptop that has gtx 680m, I-7 3630qm, 8gb 1600mhz memory. This card is basically a GTX 670 with a bit of a downclocked core and memory clock. Ive overclocked it by quite a bit and just wanted to show people my scores that i got. My card has a clock of 1045 core and 2400 memory.
3d mark 11 score P7922
http://www.3dmark.com/3dm11/5653119
Metro 2033 benchmark ultra graphics, advanced physx, DOF enabled - average 26 FPS
http://img809.imageshack.us/img809/4197/metrobenchmark.jpg
Heaven 34.5 FPS
http://img802.imageshack.us/img802/7900/heavenbenchmark.jpg
Not sure of any other good benchmarking programs to try and test this card. But thats just a small sample of how well it preforms.