There's a lot to learn here, and lots of smart people. Some cool projects, where you really get to know the ins and outs of the technology. People are pretty nice and easy to be around. The CEO is someone who genuinely cares.
Cons
It's pretty overwhelming and things are constantly slipping out from under people. Most people seem to be figuring things out as they go, which is great for a small company, but it's quickly growing beyond the bounds of that