Just had mine this morning. I essentially got the ethical dilemma question twice, one was my experience dealing with an organization that was acting unethically, the other geared towards a more personal example. To those yet to have theirs, I would definitely make sure to have at least 2 examples ready before the CBS interview. Aside from that, the expected:
-Walk me through your resume
-Long/short term goals
-Why MBA
-Why Columbia
-What do you do in your spare time
-Your background is in science/eng, how will you be able to hack it in finance/banking heavy courses
-What makes you unique
-Any questions for me
A lot of politics-related discussion too, though I feel that was more because I made very clear it was a big interest of mine. I would expect other applicants from non-wall street backgrounds to also be asked how they would fit in at the school.
The alum I spoke with was class of 03, very friendly guy who had a lot to say about the networking opportunities at the school and personal examples to go along with it. Hopefully he thought as highly of me.
Any further Q's just PM me.