Indiana still has games AT Oregon and AT Penn State. Odds are that they lose at Oregon to get the first loss. That will be Oregon's last real test. Michigan still has to play OSU last game of the season - expect them to be 10-1 going into that game. Upsets are not as common in the B1G as they are in the SEC - the scheduling quite honestly protects teams. This coming weekend will either separate two of the also rans (Illinois and Indiana) from OSU, Oregon and Michigan or make a mess of that conference. If Indiana and Illinois were to pull off the upsets, very possible that you could have the following - which will then push some SEC teams down - because they are not dropping OSU or Oregon out of the top ten if they lose.
12-0 Indiana Team
11-1 Illinois Team
11-1 Oregon Team
Then OSU and Michigan => One would be 10-2 and one would be 11-1.
There are other teams, Washington, USC that could make some noise but not sure.
This is exactly the same thing that happened last year - SEC had a host of teams near the top only to see them fall and the B1G take over.
The B1G which they would like to think they do, do NOT have the same level of parity from top to bottom in their conference.