its not hard to set different themes and apperences in XP
although the line 'Microsoft(R) Windows(R) Codename Longhorn' does kind of tell you where its from
no doubt some aspcts of longhorn/vista will come into future xp service packs, just as xp code came into 2k sp3 and screwed up many things. when it comes prepare for alot of headaches
SP3 is a long way off anyway, i only moved to SP2 a few months ago and that was bad enough.