Every even number (save Nebraska) has been a crap addition:
Pac-12 #12: Utah
SEC #14: Missouri
Big 12 #10: West Virginia
ACC #14: Pitt or Syracuse, take your pick
It's hard to get schools to move. You can convince one really good school to move, most of the time, then you have to go for ease of addition. You need a school that has ample reason to move, has minimal political impediments, and has the resources to make the move. We are floating WVU a lot of money, and we did that out of desperation. We aren't desperate now. We'd help a school like FSU because of the ridiculous buyout, and because they are a tremendous long-term investment, but if we're dead set on going to #12 right away, Lousiville is packaged up and ready to go.
It would behoove us to wait until Clemson has a new power structure in place (new AD will take charge in 2013), but again, will we wait that long? Will the new AD want to move? Also, how much better is Clemson than Louisville when you break everything out? Is it a lot or a little?
For the record, I want Clemson. I'm lukewarm at best on Louisville. I can rationalize it (as I can with most anything), but I'm only open to them if we get a blockbuster addition at #11. But there is no way that we should ever reach out to them as an odd number. Ever.