Every high volume OS will always require patches to defeat those who use their misdirected genius to try and defeat the security of a popular OS!
XP will always need patches and so will Vista. However, Vista is MORE secure than any other OS I have ever used. I have deliberatly visited known sites that use malware and found my system clean using VISTA RC2, especially with the 64 bit version as it has a secure kernel protected by "patchguard" which is what is angering Norton, etc because it would make it difficult for them. They need access to the kernel to continue what they have been doing.
P.S. Have you ever tried to uninstall Norton?