I am now running Windows 7 (x64) on my HP laptop as my main OS. First impressions weren't good when i installed under VMware Server, however having subsequently installed on VirtualBox (for testing on my work laptop) I backed up my data and replaced Vista. Having previously had major issues acquiring wireless drivers for Vista x64, I was pleasantly surprised that after installing nForce chipset drivers (in Vista compatibility mode) everything looks fine and not a sight of a yellow exclamation mark to be seen.

So far, I haven't had any crashes on the HP laptop, though for some reason its crashing a lot on VirtualBox & VMware. The new slider for UAC is much nicer (and changing settings no longer require a reboot). Despite being in beta, I'd say Windows 7 is more stable for my particular uses. All of my apps have continued to work fine (except Acrobat Reader is being stubborn)

The taskbar changes have taken a little getting used to, but similarly to Vista it's not enough to turn me off the O/S. The main thing for me is stability and I've been remarkably impressed.

Oh, and to top it all off, it's generally faster than Vista and uses less memory. So despite only having a low end laptop, its running (almost) as well as XP was despite all the Aero eyecandy.