Now that we all can agree that eyeballs on TV commercials is one of only two relevant matters driving expansion (the other being the yet-unwritten rules regarding double autobids to the BCS), let's examine the numbers of a hypothetical move of Boise and the Big12 leftovers to the Mountain West.
So, what would happen if an expanded MWC included those schools, and this expansion triggered a media deal that included TV coverage in the basic cable in the Dallas/Fort Worth, Waco, St. Louis, San Diego, Las Vegas, and then every other cable market in Idaho, Iowa, Kansas, Utah, New Mexico, Colorado, Wyoming, and those markets close to Kansas City in Missouri? (This list of markets is in the first comment below this post.)
According to TVB Research Central, that would put the MWC in range of about 14.2 million TV households, or 8.53 million cable households, which is about eight percent of the nation's cable households. (About 60 percent of American households have basic cable.)
Compare this with the current (awful) media reach of the MWC's dedicated cable network, the mtn. The mtn. is available, on cable, to less than 1.5 million (or 0.8 percent of) cable households in America. A TV deal like the one outlined above would be for coverage about 5.6 times greater than the current reach of the mtn. That's getting into the ballpark of the kind of reach contemplated by ESPN when it bid so high for the new ACC media deal. Note: I didn't say equivalent territory, but in the ballpark. I haven't run the numbers, but I expect the ACC's deal reaches somewhere like twice as many cable homes as an expanded MWC deal could.
But were the markets I've outlined in the comment below reached in basic cable by the mtn., or some other provider hoping to capture an expanded MWC's media value, I believe the rights to such a media deal would be lucrative indeed.
Compare, using the quickest and dirtiest of estimations of the media deals an expanded MWC could get: the Mountain West's current media deal nets MWC schools about $1.3 million annually. Supposing the MWC were to expand to include five more schools (Boise + Big12 leftovers), a media deal that's 5.6 times more lucrative, split 14 ways, would net each school about $4.8 million annually. That's not the princely sum Kansas is used to getting right now, but it sure beats what the Jayhawks or Wildcats could get as indies, or as C-USA members.