Pros
Very well respected organization. Great to have on your resume. This is one nonprofit that completely gets the importance of establishing connections with corporations -- for funding, support, and connections. Lots of opportunities to get involved with innovative projects, infrastructure build outs, etc.
Cons
If you're not a corp member, you won't be perceived as an equal. Ever. Organization grew too quickly and the infrastructure couldn't keep up. Very young folks with very little experience with fancy titles -- VP, MD, SVP. Just because one goes to the "best of the best" school does not mean that one is equipped to walk into a role that would normally require 10+ years of experience. Be prepared for the very long work weeks. If you have a family, are over 35, or value a life/work balance, this may not be for you.