Obviously, the biggest question for the BT now, assuming the BT stops at 12 (which, who knows?), is how will the BT make up divisions.
My guess is Delany and the presidents will a.) protect rivalries and b.) keep competitive balance ahead of geography.
Because of this, I'll bet he keeps OSU and Michigan in one division, and puts PSU and Nebraska in the other. And PSU-Nebraska begins to be the second biggest rivalry. And before you say "Yeah Michigan sucks", note that since 2008, some form of OSU, UM and PSU have finished 1st and 2nd every year save 2004.
Despite the fact that PSU and Nebraska are the 2 farthest schools in the conference (I believe), I think a natural rivalry would spark from a.) being the 2 recent expansion schools and b.) being 2 of the best volleyball schools in the country.
From there, you split up Minny and Wisky, MSU and Iowa, and Illinois and NW, and use 1 cross over rivalry, ala SEC.
So:
"3-yards" division
OSU, Michigan, NW, Purdue, Minny, Iowa
"Cloud of dust" division
Nebraska, PSU, Illinois, Indiana, MSU, Wisky
Cross over rivalries:
Nebraska - Iowa - "Trev Alberts Trophy" game
OSU - PSU
Michigan - MSU
Minny - Wisky
Indiana - Purdue
NW - Illinois
(Note you could flip Indy/Purdue and NW/Illinois and really make no difference).
Most of the trophy games say annual, and even under the 11 team format, not every trophy game was annual.