Tekhna, you'll love it. Beaker's post shows one of the many views you get from riding in Berkeley. Coming down Spruce/Euclid during sunset is breathtaking.

A couple reasons I can think of:

1. Awesome team...rides pretty much every day and a big one on Saturdays
2. Sweet climbs and descents...Mt. Diablo is close by etc.
3. Good weather. Not humid in the summer, not as cold as most places in the winter.
4. Generally good drivers. Berkeley's a small city and drivers are pretty respectful of cyclists, especially on windy climbs. Most actually wait until it's safe to pass.

Plus, grad students are treated better than undergrads! Even so, I love it!