Actually, it's been far from smooth. MS users are rebelling against the new system and Redmond has pushed back the "timeline" for killing off XP.
Article about that here in
COMPUTER WORLD
Anecdotally, I live in a tiny island in Mexico, OK. I'm not at the hub of the computer world. And I've talked to 20 people who bought computers with Vista, then took them back to have the OS removed and replaced...at extra cost...with XP.
I've heard of several companies and organizations (the only one I remember is Penn State University) telling people NOT to install the service pack because it messes things up worse.
All this from the "OS That Had No Compelling Reason To Exist"
I don't ever remember anything like that happening before. It's like something people don't want is being foisted off on people against their will and they are refusing it, but the powers that be are proceeding to give it to them anyway.
Thank God politics isn't like that.