I'm not moving to Vista for two reasons:
1) Visual Studio 2003 wont work, and therefore I can't do my .Net 1.1 development on Vista
2) Vista needs a faster, more beefed up computer than the one I have
So, why can't I just switch to Visual Studio 2005? I have it installed, and I really like using it. It's a bit slower than VS2003 in some ways, but that's something the added effectivity of VS2005 weights up for.
No, the main reason is that I can't switch the framework version we're using in our product from .Net 1.1 to 2.0 just so that I can install a new OS!
And why can't I just buy a new computer? Because a new computer is expensive, and changing computers every year because a new and better hardware configuration or OS exists isn't an option. I remember that when I first got my M4, I really felt that it was a fantastic computer with all the memory and CPU I'd ever need. I to be honest; I haven't changed neither the OS nor any of the programs I'm using in my daily work, so in theory my computer should still be up to snuff!