I can't really be sure how I feel about W8 before I actually use it, but my experience on the preview version wasn't very good. Metro simply doesn't look like it's mouse and keyboard friendly. Now, on a tablet or phone, it looks like it has a lot of potential. My greatest fear for W8 is that it will completely alienate business users. Some people I work with already have enough trouble using Windows XP, which is a UI that is quite user friendly, and which most people that use PCs have known for a while now.
Now, perhaps some changes have been made since I tried the preview versions. That remains to be seen. Also, the OS itself underneath the UI seems very good. It's basically an optimized version of W7, which is already very good.
What is means for gaming, though, I'm not sure. What I think Mr. Newell overlooks is that W8 might not be very important at all for Microsoft. W7 works very well right now, and there's really nothing that would force people to upgrade to W8. Microsoft might be actually using W8 as an experiment with a new UI, knowing very well that W7 is the fallback people are most likely to use should they not like it, not Linux or Mac.