I personally dislike those kinds of solutions where it’s hosted on someone else’s server (since I <3 being able to tinker around with it to suit my needs).
Those kinds of solutions usually degrade into "fit everything we can into it that the customers want", IMHO.
It was something I caught in July 2008 .net Magazine. I too am not keen those sort of solutions.
I posted as reference to what it might do which could then be replicated in MODx. Again haven’t actually tried and probably never will but someone might report back on it..