Same old stories from when XP was released!
"Oh noes it uses more memory than my Windows 98"
This is why I still run DOS 5 and only have 640kB of memory
In all seriousness, DON'T run Norton 2007. It's worse than spyware. However, I have found Symantec Corporate to be less intrusive and quite nice on Vista.
Everyone will have a love hate thing with antivirus programs. I have found NOD32 (dunno if there is a Vista version yet) and Symantec Corp to be the best for my use so far.