1. Recount, It would be nice if Blizzard had their own stat tracking system for raids.
2. Multiple Versions of the Default UI in all sorts of set ups.
3. Healbot, They really should create a healing interface for healers.
Now I don't know if it's a good idea for blizzard to keep nabbing Addon developers ideas (would suck if they all got scared away). But what addons or even improvements to the normal UI should blizzard add?