Well I took the plunge tonight and loaded SP2 on my primary system and my WinXP FTP server.

So far no real problems to speak of. Rebooted without a problem, did a defrag, and started up a bunch of applications. Set permissions, etc.

The only "problem" I've encountered so far is my Norton Anti-Virus 2002 doesn't get monitored. I've downloaded everything off from live update but it doesn't work. 2004 works fine on my primary system though.