Pros
You can bring your full potential to the table. You can expose yourself to practically any new technology and work it into your project. You have to be willing to put in the time, but if you're a hard-worker and enjoy learning, there are great opportunities here. But you do need to take the initiative...no one is going to just drop it on your lap.
Cons
Limited upward mobility. The organization is fairly flat and positions are stable, so its not uncommon to see qualified people work for many years before getting an opportunity to get promoted and get more responsibility. Some people do get promoted in a reasonable amount of time but keep the same job, so it's just an upgraded title. Having said that, you can move around the org to work on different things if you feel you've hit a ceiling where you are.