Haha.
Ok, the grand finale!
2007 stats
B1G played 5 ranked teams, with a 70-30 record for all opponents.
Big 12 played 6 ranked teams, with a 70-27 record for all opponents.
B1G went 3-5, Big 12 went 5-3.
So, we can say that 2011, 2010, and 2009 are all in favor of the B1G having a tougher bowl lineup, with 2008 and 2007 being a wash.
Also, the B1G has had 10 BCS bowl participants since 2007, while the Big 12 has had 7, which goes back to the thought the B1G has a tougher bowl lineup.
Thanks for the info Porkchop.