After admitting that Retribution DPS isn't quite where they want it to be in the current build of Patch 3.1, Ghostcrawler illuminates us a little bit about the direction they wish to take with the spec. He explains that the Retribution tree is one tree where players would go 0/ 0/ 71 if players could (if they put Divine Strength in the Retribution tree, he might even be completely right!).
Blizzard would like to increase Retribution's DPS but are looking into making talents in other trees more attractive, essentially forcing the spec to branch out somewhat. This would be akin to how they slimmed down the Warrior's Protection tree, which turned out to be a good thing for the class. He feels that most trees in general are "too thick," making it hard for players to put points in another tree. Hopefully, we'll see some changes in the PTR that should reflect this design direction in the near future.