Pros
It has a good reputation as a research university. A degree from here will (allegedly) get you a long way. The school is well funded, and the professors are well known. Classes are usually very worthwhile and you should be able to learn something new. Professors are given free reign on how they treat their grad students, so it could be a great experience, or the worst of your life. Be careful, and make sure you pick a good advisor or switch within the first year (first semester would be better).
Cons
Very little to do outside of lab. Little sense of community amongst graduate student population (result of no central place to gather). Long and hard work hours, little immediate reward seen. Some professors are no shows, others are constantly on your back, criticizing/attacking your work with pesky phone calls at 3am. Its seriously been known to happen here.