Just in three years, from the time I was a freshman to now being a senior, dynamics have changed a lot...
ATO handed in their charter and became a quasi-local underground fraternity called EI (Epsilon Iota, which is the name of the chapter they were under ATO).
Delta Chi, formerly the top fraternity on campus, is getting a little cocky and their numbers haven't been so hot. DTD, on the other hand, is giving them a run for their money. All great guys.
Alpha Sigma Phi has under 20 brothers, cause they graduated a TON, and it would be great to see them take a huge pledge class again. When I was a freshman, they had over 80 members.
Sorority-wise, our chapter has maintained it's spot in the top tier. Phi Sigma Sigma, who I absolutely LOVE, has come a long way in turning their chapter around and is really doing some great things. Sisters that weren't contributing ANYTHING to their chapter ended up leaving, and they went through formal rush last semester with only 30 sisters (ceiling here is 68) and still managed to get FABULOUS women. They are quickly becoming our hottest competition... which is ok, because I really adore their chapter. I'm best friends with their president

. The chapter that was at the bottom of the tier when I was a freshman has been building up their numbers and is doing quite well for itself... and one of the middle-tier sororites has fallen quite a bit and currently has under 20 members.
It's really interesting to see how the tides can turn...