I'm running 32 bit Vis~Duhh at home, which I side~graded from XP Pro, and my only real annoyance is that I sprang for Ultimate, like a dumba$$. Had some minor issues early on with driver (im)maturity. And it doesn't like to wake up if it's been asleep for a while - have to use the reset when that happens. But overall it's stable and works perfectly well - My old apps and the newer games run without issues. No BSOD's. Data transfer, etc, went fine, and it even auto detected my 5 year old Linksys router and networked itself. (Yes, I was both impressed and stunned...) It didn't like my off-brand sound card and 6 year old printer, but I expected that and had replacements lined up.
I'm planning on changing to 64 bit with my next rebuild, but that'll be something like 6 months out. My current rig is plenty good enough to wait and watch how the next gen Intel and AMD products go. Disinclined to make decisions based on Slide~Ware, Fanboiz, and Marketing blah blah blah....
At work? That's a completely different question. There's WAY too many interdependent systems for any sane IT organization with a mixed bag of systems to make the leap. Where I am we have MSFT and UNIX/Linux based servers, SAP R3, Citrix, and more custom apps than I can name off the top of my head. With the exception of point upgrades on software and the usual hardware bling, there are no current plans on changing anything on the back end at all through the end of 2008. And for the desktop, our IT guys burn everything with a standard XP Pro image as soon as it comes out of the box. Again - There are no plans to change that any time soon.
It'd be different if we were a MSFT only shop. But we aren't.
Scott