Pros
Great people to work with
Good managers (when your team has one)
Lots of services available in the building (gym, Starbucks, dry cleaners, barber, etc.)
Relaxed about clothing (jeans and polos are allowed now)
Cons
IT locks down technology choices even when there is business need
Internal teams can't really innovate
I experienced about a year of being on a team with no manager to report to