Just recently, I downloaded and installed Windows 7 RC and I've gotta say I'm impressed.
All my laptop's Vista drivers worked just fine, Windows installed most of the drivers through updates.
Everything just works, which is something I really missed in Linux, the closest it got was with Ubuntu but even then it wasn't as easy as it is with Windows 7.
It's fast, it's light, no unwanted features and an amazing new UI.
I'm a big fan of the changes they made to their UI, I like how you can keep only one window open by dragging it and shaking it, and all the other windows will be minimized, do that again and they're back.
And I like the new taskbar I don't know why no one's thought of it before.
I can safely say that M$ has officially outdone itself and that I am actually willing to pay for Windows 7 when it's released.