Too early to re-do tiers, but I figured that I might post the current Sagarin projections here.

8 teams are projected to finish within one game of .500 -- That's tight.
Schedule is huge. Michigan misses 5 wins and only 1 loss. Purdue misses 1 win and 5 losses.
Wisconsin, the 5th-best team according to Sagarin's rankings, would finish in a 3-way tie for 9th place.
Purdue, the 11th-best team according to Sagarin's rankings, would finish in a 2-way tie for 4th place.
That said, I think if the ratings are even remotely accurate, the teams in that group of ties towards the top have a lot more opportunity for positive variance (beating a team they "shouldn't" on the road), whereas the teams in the bottom of that group of ties have a lot more opportunity for negative variance.
But this is huge. Nearly any variance could affect teams' opportunities for postseason play, so every game matters.
(Note: this doesn't include any current upsets. Obviously Purdue is already -1 variance in this projection due to the loss at Nebraska, so going forward it would be a 10-10 conference record if the rest of the projections held.)