I had my Kellogg interview last week, there weren't any questions asked that haven't already been posted here. I definitely feel like interviewing on campus with an admissions officer (like I did) seems to have a different tone than the ones posted by off campus interviewers. It felt pretty formal throughout, and it seemed like my interviewer was really speaking "for" the school, as opposed to representing her own experiences.
I stumbled on a question about my leadership style, even though I had prepared for it, my mind went blank, but do think I was able to demonstrate my knowledge, fit, and excitement about Kellogg. Also, the weaknesses in my interview I think I expressed very clearly in my essays. My nerves got to me a bit.
If responses started coming out at the end of November last year, I guess we can't be that far away from hearing some early results.