I answered you I'm sure. (not sure where the post is)
IMHO - No, not for the average user.
There is more candy and more security and more hand holding, but come on - for the average user or advanced user unless you have a ton of cash to spend on a new DirectX 10 video card (currently only Nvidia has one that I'm aware of and it's a $500 card) there just is not anything compelling to me to warrant the cost of the upgrade.
If you're buying a new computer and it comes on it okay but I'm not going to pay for it on my own. It also has much higher hardware requirements than XP.
XP had a few things that an average use would like and some that IT really likes. Doing WMI remote scripting is better in XP than 2000 (Vista will have more too, but not enough reason to update for me).
Go check out the top 10 reasons this site has for upgrading.
Most of it is marketing hype (imho)
http://ezinearticles.com/?Top-10-Reasons-to-Upgrade-to-Windows-Vista&id=403504.
