I would not want a laptop with a graphics card based on a G84 or G86 (8600M is based on a G84M). They are known to overheat and fail at any unacceptably high rate. See
http/arstechnica.com/hardware/news/2008/07/nvidia-denies-rumors-of-mass-gpu-failures.ars (also check the article linked in making the allegation).
Here's the truth about trying to play the latest and greatest games at anything more than the lowest settings (if at all): you can't do it unless you pay through the nose (>$2000) and buy a mammoth computer. Even then, performance will be limited by the difficulty in keeping the machine cool. And within 18-36 months (at the outside), your hardware will no longer be adequate and there will be limited means of upgrading.
The idea of an affordable laptop that is both portable and capable of high graphics just doesn't exist. And any compromise you make will only last 18-24 months. The very expensive desktop-replacement laptop that I got to play Doom 3 in mid-2004 at medium setting was unable to play Fallout 3 even on the lowest setting in late 2008 because of the GPU and there was no way to upgrade. Had I owned a desktop, I could have easily extended the life of the PC as a useful gaming machine by a few years by upgrading.
Computers are so incredibly cheap right now. By an inexpensive laptop to use for school/work/whatever and buy a relatively inexpensive desktop for gaming. You can easily afford something both for under $600-800, rather than spending $1200-1500 on a laptop that will be mediocre gaming PC now and next-to-useless within 2 years.