Pros
Perks obvioulsy (now I know why they have so many perks.. may be just to lure the best of industry talents and squeeze from them as much as possible), brand name, unlimited PTOs, lots of potential to learn.
Cons
The entire company is trying to double up profits year on year and so the pressure, really trickles down from top to bottom, You will regret for having joined this place, if only your team is being newly set-up be it regionally or centrally and your manager is relatively new. "Can we rush this out?" was the most frequent phase that I've heard in the organization! Honestly too much work load gives you no space for creativity and all that you try doing is to meet crazy deadlines! I've done much better work in other places and definitely not in Twitter!