well, the thing is, statistical rankings don't mean a whole lot. Its all about Wins/Losses, and who they are against. If you go undefeated in the big12 and have the lowest offensive numbers in the conference it won't make a difference, you will be a top 5 team.
As far as polls go, BCS is for all the marbles. AP is just an "opinion poll" by the press, the BCS determines the big bowl games.
so if we had the option to be #1 in the BCS and #4 in the AP, or #1 in the AP and #4 in the BCS, we would want the #1 in BCS.