We had some good times with AMOv3. We built on the AMO foundation we had and expanded the feature set offered to include crazy stat tracking, an API, massive scalability, etc. etc. Since AMOv3 was released we've fixed over 2500 bugs.
That huge feature set hasn't come without it's consequences though. AMOv3 is two and a half years old and starting to show it's age. It's becoming difficult to add features the way we want because we're depending on legacy code that needs to be replaced.