Pros
Although I'm pretty young, I've worked at quite a few places. Demandforce is by far the best place I have ever worked. We're actually voted one of the best places to work in the bay area. I think it's because there is such low turn over and they are great about recognizing people who are working really hard and doing great work. Those people move up really quickly and it's not unual for people to be promoted each year they are with the company.
Cons
It's very competitive. Everyone is such a rockstar, you really have to be extraordinary to stand out. This isn't really a con but they throw a ton of fun events. Keg parties in the office every other Friday. If you aren't into the whole work hard play hard environment, Demandforce is not for you.