I have often thought of my MBA as a vocabulary course that would help to bridge the gap between the service and civilian worlds. I wholeheartedly agree with many of the comments made above - when I made the choice it was about differentiating myself from the pack. That being said, an MBA in Project Management combines well with my tp and P.Eng. background...
I guess it's all about where you want to go. I've ran into some rather sharp people in my program who are using the tools and techniques that we are taught to good advantage. On the other hand, there are those who blindly apply everything and wonder why it doesn't work...much like life, really...