Saw posting on my university career site. Submitted my resume, cover letter, and other info on online application and was emailed back for a phone interview within a few days. Interviewer was nice and asked the same brainteaser sales tax question that others got. Aced it with no problem. Other fairly stock behavioral questions followed, although at various times the interviewer would quiz me on some very specific part of the website, e.g. what three countries do we source our diamonds from?, etc. I certainly reviewed the company's website, work, and business model before the interview (e.g. founded by a married couple seeking ethically sourced gemstones, etc.), but the interviewer seemed to expect that a candidate would remember lots of obscure facts.
Anyhow, the interview went about 45 minutes or so and I got an email rejection about two weeks later, so at least they do a good job of following up. Overall the interviewer was nice and polite and followed up, but it does seem they are nixing otherwise great candidates for not being experts on the company's niche work with "I gottcha" type questions.
My one tip would be to let candidates (or hires) grow into their knowledge and love for the company. Don't expect that a candidate must show overbursting love for you right off the bat; that grows with time.
