The T7600 is as capable if not more than an E6600. So even in desktop form Laptop CPUs can keep up, and don't forget Voodo and Alien's desktop chips in mobiles.
There's no limit to putting the GF8800 in a laptop other than the desire, and potentially profitability.
If they can put a P4EE or FX60 in a laptop with 2 GF7900s in SLi then a single GF8800 with a good CPU you should easily doable.