After several emails with two different TFA departments in two different cities:
Two interviewers over -the-phone. Very nice, introduced themselves and the career path through TFA.
Behavioral style interview.
Common questions describing yourself and your professional background. PREPARE using their website and the job description!!!
Be sure to discuss your background's connection to TFA's mission and core values.
Interview went really well but I know it did not help that I wasn't enthusiastic about relocating!