I think Bisping should prove himself a bit more before stepping into the octagon with Griffin. Bisping has had what, one UFC fight where he won TUF? And geez, pretty much the entire world had him marked to win that fight. He has an 11-0 record but the light heavyweight division is so deep that I still think he needs to prove himself.
Griffin had 2 fights before he stepped into the cage with Ortiz. I think Bisping should have at least one "winnable" fight (although no UFC fight is a cake walk, just ask Ed Herman) and then a fight against someone he should beat, but might have a tough time. If he wins both fights, then sure, allow him to face Griffin.
I just don't want Bisping being thrown into such a high profile position this early when it could only lead to his downfall.