Pros
I received a competitive offer from Linkedin, got to move to a city of my dreams, and had to leave what is undoubtedly the best job I have had since graduating college (even Linkedin isn't as much fun). Keep in mind this job will challenge you, but all the while you have a wonderful supportive team of mentors around you to help you succeed. And if you are in it for the long haul, their career path is much faster than other large software companies (I was promoted after 8 months). Extremely competitive salary and a lot of fun - just wish they had an office in Mountain View!
Cons
Honestly the challenge is being in your mid-20's having to pitch C level executives. I enjoy this though, especially because you are able to learn each client experience you have.