I'll start by stating I'm a long time java developer recently turned to rails/flex. The other day I was looking at a framework called parsley (
http://www.spicefactory.org/parsley/). They have developed many features from spring into AS3. I LOVE the dependency injection part (interceptors are very nice too). Thier MVC isn't nearly as mature as pureMVC. When I start thinking how nice it would be if I could use dependency injection with pureMVC, I start salivating. Wouldn't it be cool if you could do all the registering and mappings via an xml file? Registering commands to events, doing the mediator-view mappings, all that stuff would be beautiful, and greatly reduce the amount of AS3 clutter in my project.
I know it probably won't happen. But one can dream can't they?