Pros
Exposed to all the workings of an overall exciting and positive company (owned by Comcast) that includes SNL, Tonight Show w Jimmy Fallon, lots of cable channels (USA, SyFy, Bravo, Oxygen, COZI, more) and of course tons of News. 30 Rock is a great place with lots of history, good cafeteria, and prime views of the Rockefeller ice rink and Christmas tree. Great benefits, company phone, generally pleasant environment for such a huge corporation.
Cons
Specifically for IT- it's pretty amazing how nickel and dime and low-priority it seems deemed except everyone always needs help right away and lots of hand holding to understand even how to use technology. It also has a very healthy dose of nepotism which makes changing roles (jobs) within the company next to impossible on merit alone.