Surprisingly little how much I care that they are gone. The only reason, like said above, is that it could contribute to the conference crumbling and us getting screwed. Otherwise, I really don't care. Could care less about CU. aTm falls into the same category as NU, but probably care even less except for contributing to possible conference failure.
One thing I'm surprised with these fanbases is how much they support the moves. I would have a hard time throwing away a hundred years worth of rivalries for a little extra money or [insert other reason here].