You know what, you can argue this all you want. The answer is going to ultimately be what user interface do you want to accept.
I guarentee you I can counter most if not all arguments you have for using XP by stating you can do the same thing in 2000 or 2000 with a freeware add on.
Vista isn't inherently evil, vista doesn't waste memory, vista isn't going to rape your mother, just get the damn OS if you want. If you are spring loaded to complain about vista, then stick with xp, us vista users don't care if you stick with xp or not.