My interview yesterday went extremely well, if I say so myself. I met with roughly the entire population of central Indiana, and feel I made a favorable impression.
But who do I send the thank-you note to if I interviewed with an entire department (12 people in total)? The head of the department (who’s in a separate building) or the point-person I’ve been in contact with the whole time? I’d guess the latter. But who do I address it to, “John Q., et al.”?
IMO, send one to each of them. Address the letter specifically to that person, but in your letter, include a statement to the effect that you’d like to thank that person and the others for the interview.
Typed on bond paper. Think about it as a cover letter but post-interview. IIRC from the job-hunting books I’d been reading before getting this job, you should thank them for their time/the opportunity to meet them or learn more about the position, clear up any issues that you felt you might not have been made clear, and express your eagerness to hear back.