Pros
The culture is, at times, fun. And you will meet fun people. If you're looking to be a career frat/sorority, it can be entertaining, but not sustainable.
Cons
They'll lure you with a fun environment, then suck your soul dry. You will be mandated to work 12 hour days (regardless of the effectiveness). You will be trained to sell, but they will not invest any further in your career development. The metrics that sales people are held to are often mis-aligned, and as soon as you grow accustomed to them--they'll change. Toxic sales environment. When I left Groupon, there were 19 salespeople on my team. Now, 4 months later, only 4 of those people are still employed at Groupon. We gather to celebrate each time a new one quits. If you take a sales job hoping that it will turn into a Marketing Career....you are being mislead, along with 30%+ of your colleagues.