After years on staying on, brilliant but slow, XP I was happy to upgrade. However my friend's experiences with Vista were abysmal to the extent that he downgraded to XP again....
However I can safely say Windows 7 is fantastic for me. Think of it is Vista, perfected! However it does have some new features over Vista which, like many Window OS features, are a nice addition but taking as granted.
Coming from a gamer perspective this is also great as it runs faster than Vista and XP but also gives you access to DirectX 10 and 11.
All in all I would give it 4.5 stars, however Play.com only lets you give whole stars so 5 is in good order!