Perception. We live in a media driven society, and sports more than anything else is tapped into that media. Just look at how ESPiN's fingerprints are on realignment. And in this media saturated culture, branding matters. It has nothing to do directly with on field performance; it has to do with popularity and converting that popularity into $$$ (which may indirectly affect the product on the field in the future).
Look at the Rays. The re-branded themselves. Or the B1G.
That's why I think its a big deal; I think its weak in terms of a brand.
I get all that, but there's more to branding than a name. Regardless of the name, this is now a brand new conference, and it's going to be seen as such.
The perception (and reality) is that we are now in a conference full of teams that no one else wanted. I'm hard-pressed to think of a name that would do anything to overcome that perception, and almost every name I've heard suggested by fans has been in jest.
In my opinion, I'd dislike any name that has a number or a geographical region, because they limit what you can do as far as expansion. I'd also dislike any name that sounds too grandiose (e.g. "Big" anything), because that just invites derision. I think you just put a solid name on it, and go about trying to change the perception on the field.