Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.
If you check out some specific benches. Some games like the very popular CoD don't like a poor link speed at all.
I think one shouldn't try using a CF/SLI or MulitGPU card like the 6990/590 but for a 560 ti it is fast enough.

At first one needs an external monitor. I wonder if they give us some optimus driver that would enable a write back to the Intel GPU framebuffer. Shouldn't be too hard, maybe a bump in performance but the lower res notebook screen should make up for it.
 
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.