I applied online. The process took 2 weeks. I interviewed at TNTP in Mar 2011
Interview
The process is very much similar.I too completed the hiring process exercise doing (the exercise was really a lot of work, and I was really confident to get an interview call). And so I got interview call, my interview went great. Then I was called for 1:1 interview. It was also good. But they finally said NO. I somehow felt that they are not seriously look to hire a person. It seems as if they are interviewing people just for a sake of interview...under some contract. They do not intent to hire. Please Please do not waste your time if you have some other important thing.
Don't loose other options just because you need to complete the exercise or attend TNTP interview.
I applied online. The process took 2 weeks. I interviewed at TNTP in Jun 2014
Interview
I applied at the end of May and they called me in about two weeks to schedule a phone interview. Half of the phone interview was a role play of the case study they sent a few days before. I found that the case study they sent and the role the interviewer played were not consistent. It seemed that the interviewer did not read the case study carefully. I also found that for this particular position the format of the interview was pretty useless and that they were not testing the actual skills needed for the job. I kind of stopped the interview myself because I felt it was a waste of time for both of us. I don't think TNTP were clear with what they were looking for in terms of tech position.