One thing that annoys me about XP is it's Add or Remove Programs list.  It just gets really crowded over time as more and more software gets installed and, well, gets to a point where it is easier not to uninstall some unused program because it's tedious to locate it in the list.  Windows Update doesn't help either because every update gets added to the list as well.

Please add categorized view for the list so we don't have to see applications, development tools and components, gadgets, utilities, and patches next to each other.  While you are at it, add Recently Installed category as well and place it at the top of the categorized view.  Oh, yes.  Entries should be able to appear in multiple categories.  As far as taxonomy is concerned, I can live with one Microsoft dictates.