I'm posting on a Windows 7 64-bit machine now. Download this, you'll love it. I have both new hardware and older printers/scanners hooked up. Everything works perfect, no driver issues at all.
I think Microsoft has been very smart about this release. They listened to all the user feedback and I love the new system. When their servers had issues with the volume they added a ton more servers. I was able to download after the server buff at 2mb/sec which is vastly faster than I could torrent it.
Taking off the user limit and getting this on more machines is brilliant because I feel that anyone using it will love it. In this case Microsoft shouldn't have anything to fear that I can observe to this point. I hope the bad press with Vista should be over because you have to make a really big stretch to find issues. For the record I liked Vista but this is way faster, prettier, less confirmations for actions et cetera. This was the smoothest OS upgrade that I have ever made, dare I say nearly as easy to upgrade with as few problems as I'd expect from Apple.