security... hmm.. yeah.. you will never get a microsoft product that is secure. End of story.
deployment.. don't know what you mean..
manageability, so what's wrong with this in XP
performance .. for all I know Vista needs better hardware to run. More ram etc, therefore I'd say performance is worse than with XP.
I never liked Vista, never saw the point in upgrading. But if people want to use it then I don't mind, it's their choise. If they like Vista more then they should use it. But I'll be sticking with XP and kubuntu for quite a long time.