Actually, the name being mentioned a lot more for the USC job is Jamie Dixon. This has some legs. Will it happen? Who knows?
Dixon grew up in Southern California, went to Notre Dame HS in Sherman Oaks. His wife is a USC alum, and USC has a really tight alumni network. The SC job has always been considered one where the right coach could be a huge winner. Great recruiting base, media center, weather, etc. Of course, UCLA basketball is LA's showcase program, while SC football is king, but LA is big enough for more than one program. SC built a top facility a few years ago, so now many feel the program is ready to win. Money is not an issue, as SC has tons of it, much more than Pitt. There are also questions about Pitt's move to the ACC, but none of us really know what the furute brings, or how Dixon feels.
Speaking to some USC alums, one drawback to Dixon is that he coaches like Ben Howland, slow down, good defense & physical, where West coast players want to play more up tempo. Possibly, Dixon's coaching style at Pitt was a result of him (Howland too) feeling that Pitt was not going to attract flashy high scoring players, and coaching the way he did was best for Pitt.
Anyhow, USC has a number of names kicking around. Lavin doesn't seem like a big candidate.