I applied online and hadn't heard anything for a month. I then chatted with the AT&T recruiters via the attjobs/careers recruiter chat on Facebook, and then received notice that I'd get an interview in two business days. While the process went well at this point, I was not given clear information where the position was located (location: Missouri) until the interview. I couldn't relocate and had to decline going further in the process. Overall it was a positive experience because the recruiter had allowed me to talk with her if positions open up in my area.
The "interview" was to be a phone call (really a conference call, but you're given the info for the software or phone app) where we discuss the program, position responsibilities, general interests and resume. After that would be an interview if you qualify.