A well educated, talkative people have informed us that Geforce 8600GT actually have a problem. It is not that critical but G84 based Geforce 8600GT has a bios problem.
Nvidia is working to fix it and if all goes well it wont affect the launch at all. Geforce 8600 GTS are bug free and are getting ready for rock and role.
Nvidia is ready to rock and role these sub $200 cards and these ones will goes against RV630 based cards X2600 ones scheduled for May. If all goes well for Nvidia, you wont even know that the problem existed.