Access to d-list celebs, opportunities to be part of minor events, and if you're lucky, comiccon. also the opportunity to pick up lots of useless corporate jargon and attitude from egomaniacal execs who have become socially maladjusted from lack of work-life balance.
Cons
Everything is a crisis. Everything is make-do. Everything is pitch-in-for-the-team-at-the-expense-of-your-personal-life. If you don't have a life of your own, Syfy will give you one-- and then slowly starve it.