Ran across this podcast through the Directions Magazine email...
http://www.directionsmag.com/podcasts/gita-reorganizes-a-lesson-for-professional-geo-organizations/255949
GITA has reorganized to a completely volunteer-based organization - not so different than MAGIP.
A point worth noting from the podcast: local professional organizations are doing much better than national ones.
The main question raised: what can a professional organization offer that isn't already being provided somewhere else?
What is it that MAGIP provides? I would say a sense of community - a forum for discussion and collaboration. I think we put on great conferences/tech sessions and offer web services that are tailored to meet the needs of the Montana GIS Community.
What could we being doing better or more of?
How do we prevent volunteer fatigue and keep the membership active and motivated?