We already have two belts anyway... it's called the interim belt. Seems to work fine as it is right now.
Also, there's not enough contenders for the belt as it is. Two belts would definitely not help.
I think upgrading Condit to an actual champ, and having him rematch Diaz would be better than waiting around for GSP.
Then when GSP comes back the onus would be on HIM to reaffirm why he was champ in the first place. GSP could beat a few guys and sometime in 2014 perhaps the two champs would fight.
And a second champ at MW would do wonders for the division, which is stagnant as hell right now, and has a champ who isn't fighting again for 6 months while Belcher, Weidman and Bisping are all worthy contenders.