There's little to recommend it except that the visual appearance is more sophisticated and flexible than XP.
With the right config it can perform as well as XP, but then you loose all the extra features and functionality that were using up the extra CPU cycles and extra disk I/O access bandwidth.
All in all there is no justification for Vista; but this is the case for the majority of software upgrades, which are also often no better than before and introduce new faults.
I got Vista a year ago on a new laptop just in order to become acquainted with it. That's about all I achieved over and above what I would have got had I installed XP on this laptop.
XP is getting more and more reliable in my view. By the time it is End of Life'ed for good, it should be just about ready for use
