If it's any consolation, a number of my larger clients (generally 50,000 employees or more) only just completed their transition from NT to XP at the end of 2006, and one is still doing it, because they do not like to have to change everything. I am unlikely to recommend Vista from a usability perspective in the next 2 years, and unless they sort security, much longer.

Of course this is just my opinion, my employer may or may not have the same one:-)

We are definitely seeing an upturn in offices willing to try open source! Because of the general annoyance value of Microsoft.