Well, I have no doubt in my mind that 7 is better than Vista and XP (I think Vista is better than XP)
I really think everyone should just get a mac, but as all macs except the macpro use mobile GPUs, its not much an option for gamers who have price limitations. I was very fortunate to be able to sell my gaming PC for more than what it was worth, and replace it with a macpro, which I do all my gaming on via bootcamp (with vista). When the opportunity presented itself to get such a great computer, I couldnt resist. I had fallen in love with my macbookpro and OS 10.5. And having used ipods since they came out, and owning an iphone 3G, i have had a very good experience with apple.
Back on topic... I think win7 is a very necessary upgrade for those using XP, vista I find stable, fast, and easy as long as you dont have a lot of programs messing it up, but i think win7 will still have those problems. I have never used vista as a primary OS, before getting my gaming computer (which as mentioned I have since sold) I had an old desktop with XP and my macbook pro.
I think after users really start using 7, they will find themselves buying registry and clean up programs, and will be just as upset as they were with vista. Marketing will only get you so far microsoft. If apple drops prices, they will take the market.
EDIT: P.S. anyone else seeing the "click here to fix windows 7 errors and optimize windows 7 performance"? LOL