A few Windows 8 Questions

(1) If I use Upgrade Assistant on my Win7 machine, do I have to install Windows 8 on that hardware? Or can I wait to install it on a PC I'm building later?

(2) Is the upgrade license you get from Upgrade Assistant usable on more than one machine?

(3) The machine i'm building is a gaming PC and HTPC. What do you think of Win8 for gaming right now, and as a 10-foot interface?

Thanks brethren.