It appears that there are two factions on MU. Those of us who want MU to function as something like a lower-level MO, and some of us who want a less-focused general math forum.
The main difference here is how picky MU should be with its questions. I summarize them as follows:
Lower-level MO: Questions should contain mathematical content at any level, but should be focused explicitly on mathematics. This appeals to students enrolled in math classes (or classes in allied fields(physics, chemistry, economics, etc.) or in an undergraduate math program.
General Math Forum: All questions are welcome if they are math-related, but not necessarily math-focused. This appeals to the general public, but appeals less so to students.
These two factions have different enough ideas that it may warrant a fork of math.SE.
Here's a list of people to read on meta for a good idea of how each faction would like math.SE to run:
General Math Forum:
If I've gotten your position wrong, please feel free to edit this post and fix it. If you'd like to elaborate on your own position, please feel free to leave a comment or an answer.