I think those hoping we stay in the BIG EAST need to take emotion out of it (myself included). It just doesn't make sense for a long term survival standpoint (and I hate that because I love the BIG EAST) to turn down a P5 invite.
The BIG EAST (sadly) can't offer what a P5 can from a financial standpoint, and the way conference realignment is going, I'm not sure the BIG EAST will be around in its current form in 5 years (if this happens and we stayed put, who knows what happens next).
Is the Big 12 a hand-in-glove fit like the ACC or B10 would be? Hardly. Hell, I'm sure the athletic department would love to stay put, but they have to ensure the long-term viability of the brand - and all it stands for (champions, integrity, leadership, winning) - at all costs.