Pros: you will have so much to learn and you'll have more confidence in yourself after the internship, "free lunch, cup-cakes, ice-creams", "happy hours", "office yoga" will make you believe "have fun, or go home"
Cons: seriously, you have to study/work hard to stand out...coz ppl there are all very smart:-)
I had my great internship at Pulsepoint this summer. It is a great place to learn, build-up your skills, and most importantly, have fun. As an intern, I was given a well-organized and planned intern plan on my day 1 and was assigned with a mentor. My mentor was very sharing, smart, patient, and responsive. They asked a lot "what you have learned" rather "what you have done for them". I felt I wasn't just an intern, but a part of the team and a part of the "culture". Little dreams matter and "interns" matter!