Pros
Teach for America is a very prestigious, selective program that is working to end one of our nation's greatest injustices. They train their corps members very rigorously (sometimes TOO rigorously) and are very proud of their success. Working here is very rewarding and if you're interested in education for the long-run I would definitely suggest starting off as a TFA corps member. Having the experience of being a corps member really gives you an advantage in professional growth in the education field. The pay is decent depending on where you work (teacher's salary), and you meet a lot of very passionate people from across the country.
Cons
TFA often speaks of the experience as a difficult one, but they rarely go into the specifics of why it's so difficult. Don't expect to end work at 3pm like you may have believed teachers do when you were growing up. Especially your first year of teaching, expect to work upwards of 12 hours a day or more. Those 12 hours are grueling, and you'll probably come home exhausted from having to deal with poor administration at your school and disrespectful students. Also, once you've been in TFA long enough, everyone talks about the achievement gap using the same buzzwords and offering the same solutions. Often there isn't much creativity in approaching the issue. For your first year of teaching (especially your first semester), there will be virtually no work-life balance for most. Many of my fellow corps members considered quitting (some did) because it was too much work and too stressful. It's not an easy job, but you have to really consider it a "calling" if you want to join. Don't join TFA because you think it will help you get into business school (it won't) or will look good on your resume (it's not worth it). Join TFA if you really believe in it's mission and helping kids.