Interesting topic. Out here in the PNW we would use "Texas" and everyone would know what it meant (in context of course). So: "Did you see the Texas - Texas A&M game? They've gotta fire Jimbo after that shitshow." (As college football fans, "A&M" would also get that point across; with our group "aggy" is understood.)
Washington is nearly always "UDub." More formally, Washington works; on CVs, etc. "University of Washington". For other system schools it's UDub-Tacoma, etc. WSU is Wazzu. (One of their former presidents tried to put a stop to that, saying it wasn't dignified; one of the few things to bring Huskies and Cougs together was laughing him out of the state.) UC-Berkeley is Cal. I don't know what the grads there use, but here Arizona is usually "Zona", sometimes UA.
The old Big-8 was messed up. Nobody has ever been able to explain to me CU, NU, MU, KU, OU.
Also interesting was the comment on Wisconsin - I've always just said "Wisconsin" but with a system that size, UW-Madison makes sense.
I suppose most places other than P12 or B12 country, OSU = Ohio State; here OSU means Oregon State and the others are "Ohio State" and "Oklahoma State". I'd imagine it works the same way down there for OSU = Oklahoma State.