I have said it again and again. I think Vista was not a bad OS at all. Not the greatest but somewhere between good and great.
While I missed very early teething issues, I did catch a few. I didn’t get to use Vista until I completed my military service, in summer of 2007. This was the first and last OS that caused me to say “wow” on first boot. It just looked so great! Sure, Linux had all the bells and whistles and XP had WindowBlinds but they never looked as clean and classy. But to get that far, I had to remove some RAM as setup hung when you had more than 2GB… And then I got a BSOD due to Bluetooth stack. 🙂
I did keep on using Vista personally until a few months after 7 came out.
I did plenty of Vista rollouts in 2008 and 2009 and… it worked great. By that time SP1 was out and drivers had stabilized. On most of hardware it ran just fine. Maybe not as fast but XP the difference was not noticeable and people actually liked Vista. For most of enterprises, I think it was a mistake to skip Vista. As tooling and many OS concepts had changed considerably, I saw many people complaining after Windows 7 release. They hadn’t even touched Vista and were surprised how similar Vista and 7 were.
Security was better. UAC was actually great (it had some nice side-effects). Quite a few features actually became usable compared to XP. It had some nice features for sysadmins that went relatively unnoticed. On the other hand, early tools sucked big time. Later WAIKs were much better and by SP2 it pretty much looked as it does today.
I switched jobs in 2010 and didn’t get to professionally touch Vista since. Kind of sad actually. Technology was solid but teething issues caused an unrecoverable PR nightmare.