Pros
You are able to have a hand in a lot of different projects--they even recruited me for helping to name books, which felt pretty cool. If you have an interest in books, publishing and editing, this is a great place to learn a lot about the process.
Cons
When I was there, there was a bit of a shift in intern coordination, so at times it was hard to know who to go to for overall intern questions, but that was mostly a situational issue; with time, we got into a groove.