OK State would be number 2 had they beat Iowa St. Alabama would still have been the 2nd best team IMO, but OK State would have done enough to warrant the number 2 ranking.
Oklahoma State would have split the computer polls with LSU had they been unbeaten. Their SOS was the best out of any of the high ranked teams, including LSU. They would have gotten all the 2nd place votes as well. Alabama would have been closer to Stanford than Oklahoma State in the final BCS rankings.