YEAH! Another SFSU Alum over here! The SF State system is very small but close-knit, because we have a kind of siege mentality

due to the anti-greek attitude of the campus. The NPC sororities are doing quite well in spite of it.
I agree with Glitter650 that the chances for a spring rush next semester are much lower than usual--all 3 are pretty close to total. I was told Alpha Gam is returning with around 40 girls, and I know the other two chapters are also at a very healthy size.
As for USF, I visited their campus and met the Panhellenic several times. There was a chapter of Delta Zeta and Delta Phi Epsilon. Both chapters seemed to be doing well, but I don't know what the current status of the greek system is on that campus.
Good luck in whatever you decide to do!