Later, I'm going to discuss the bowl pictures in various conferences. Before that, however, I think it's important to address some misinformation being peddled by a number of outlets concerning bowl eligibility rules. The most important think to understand is that as I discussed a few weeks ago, being bowl eligible at 6-6 is not the same as being bowl eligible at 7-5 or better. The NCAA rule, generally, as set forth in NCAA Bylaw 30.9.2 (.pdf, p. 372) , is that a team is bowl eligible only if it has a) six wins and b) more wins than losses. In 2006, the NCAA adopted an exception to the bylaw accounting for the twelve game season. As I noted in the post linked above, that bylaw exception (184.108.40.206) provides:
an institution with a record of six wins and six losses may be selected for participation in a bowl game if 1) the institution or its conference has a primary contractual affiliation which existed prior to the first contest of the applicable season, with the sponsoring bowl organization. In the case of a conference contractual affiliation, all conference teams with winning records must be placed in one of the contracted bowl games before any institution with a record of six wins and six losses may be placed in a contracted bowl game; and 2) all contractual affiliations have been fulfilled and all institutions with winning records have received bowl invitations (either through a contractual affiliation or as an at-large selection.
This rule sets up a hierarchy in which 7 wins trumps 6 wins and conference affiliation trumps at-large. I think the best way to think of this is through the eyes of a bowl selection committee. Here is the order in which a bowl may consider prospective teams:
1) Teams with seven or more wins and from an affiliated conference;2) 6-6 teams from an affiliated conference;3) At-large teams with 7 or more wins;4) At-large teams with 6-6 records.
A bowl can move down the hierarchy only if every team at the higher level has a bowl invitation. The most common scenario advanced recently is that the Motor City Bowl will take the local school, Michigan State, over IU, even if IU is 7-5 and MSU is 6-6. The above hierarchy makes clear that that cannot happen. If IU is 7-5, IU will be a "tier 1" team. If MSU is 6-6, MSU will be a "tier 2" team. The Motor City Bowl cannot select a tier 2 team if there remain tier 1 teams without bowl invitations.
On the other hand, a 6-6 team protected by a conference tie-in trumps a 7-5 at-large team. For instance, suppose that Iowa and IU both end up with 7-5 records, meaning the Big Ten would have eight teams with 7 or more wins and only seven bowl tie-ins. Suppose that the MCB selects Iowa. That would make IU a "tier 3" team in the eyes of other bowls. Suppose that the Texas bowl, the #6 tie-in for Conference USA, really covets IU. If there is a 6-6 C-USA team without a bowl bid (a tier 2 team), there is nothing the Texas Bowl can do about it. The Texas Bowl would have to take the 6-6 C-USA team over 7-5 IU. This isn't necessarily because of the NCAA rule, but because bowl contracts generally require that the bowl take any eligible team from an affiliated conference.
The nightmare scenario for IU is 6-6. If IU finishes 6-6, the Hoosiers almost surely will not receive one of the Big Ten's bids. If that happens, IU will be a "tier 4" team, eligible for an at-large bid, but only if every single Division I-A team with a winning record has a bowl invitation.
In sum, if someone tells you that a 7-5 IU team could lose a bowl bid to a 6-6 MSU team, that person is wrong.