Surprised we haven't gotten into the "UM" battle yet.
Claimants:
University of Maine: You never really hear "UM." I think the preferred these days is "UMaine" in the style of UMass or UConn. The website is "umaine.edu" and NOT "maine.edu" which refers to the whole system. As a note: UMO is not an appropriate abbreviation for the school. It was for only 15 years, as it stood for "University of Maine-Orono." However, Because the Orono campus is the flagship, and on a different level than the others [UMaine Fort Kent, UMaine Machias, UMaine Portland-Gorham (aka Univ. of Southern Maine), UMaine Farmington] as a national research university, it is actually THE University of Maine. UMO seems to persist, despite the university's (and especially the faculty's) attempts to stamp it out.
University of Massachusetts: Again, you never hear "UM." It's always "UMass." The Hockey East fans among us will often refer to it as "UMA" to distinguish it from UMass-Lowell ("UML"). That really makes no one happy, as the UMass fans make the same argument UMaine makes above (flagship), and UML only reluctantly took on the "UMass" moniker in the 1990's.
University of Montana: I think this is the most common "UM" reference around FCS. I'm okay with it, as a UMaine fan. "UMontana" or "UMont" just sound funny.
Non FCS claimants:
University of Michigan: Ubiquity breeds acceptance. Even across the hockey world, where Minnesota is arguably the larger power, Michigan is the true "UM."
University of Minnesota: Michigan being called "UM" has to really stick in their craws. One of my favorite parts of the college hockey season is when Minnesota makes its annual trip to play Minnesota-Duluth ("UMD"). The scoreboard will list the visitors as "UMTC" to represent "University of Minnesota-Twin Cities." Hand wringing ensues.
University of Miami: I'm sure some of our Floridians can weigh in, but I rarely hear "UM" for Miami. They seem to really be pushing "The U" as their abbreviation. Of course, as a hockey fan and a northerner, I recognize Miami University as the true Miami anyways (#1 in the nation in hockey right now).
University of Mississippi: "Ole Miss" is ubiquitous anyways, I don't think they stake any claim to "UM." As a side note, I heartily endorse Admiral Akbar as their new mascot:
http://www.huffingtonpost.com/2010/02/2 ... 75349.html . "It's a trap!"
University of Maryland: I'm sure it has happened, but I don't think I have ever heard "UM" for Maryland.