The 50 hour work week, the micromanaging, "clock in/clock out" type of atmosphere, lack of clear advancement opportunities, lack of trust and communication from managers to staff and between departments
The biggest downside to me was the lack of trust. As has been mentioned in numerous reviews now, the marketing department exists to build links and push out reports no one reads. As basic as that sounds, they will dictate how you do every step of the process. It's frustrating and annoying because, last I checked, we are intelligent adults who deserve to be treated as such. There could be a little (a lot) more freedom given to let individuals complete the jobs their way.
And those hours - I won't beat a dead horse with this, but they are terrible.
Also, if you work in marketing, prepare to have sales "yell" and get extremely frustrated with you over things you don't even have say over.