Yes, games will run fine, and both AMD and Nvidia posted drivers especially for win 8.
On another note:
I'm really dissapointed in this preview(and perhaps windows 8 as a whole) after using this install.
For Metro, I expected to have this nice and useable interface, in which i could do basically all i could at the desktop(with the proper "app" atleast)
Instead i get this 90% useless interface to which i'm bound, since there is no visible and easy way to disable it. Furthermore the apps from which I expected the most, like messenger and mail dont even give 10% of the functions i was used to from windows live essentials. And then when you think, ah well, i'll just log off, there doesnt seem to be a way to actually log off, only appear offline. This interface is fine, for my phone, but for my PC I want to be able to do a lot more than that it currently offers me.
If only they included the simple "shutdown Metro UI" option, everything would've been fine, but this... I guess we'll have to wait for the "windows 8 professional review", or atleast some news about some version of win 8 having the option of turning that darn interface off.
This is coming from someone that was really positive about win 8 untill today