Had my interview this past weekend and I think it went very well. This was my first interview with an alum and it was very conversational. Touched upon the usual questions, nothing out of the blue. I would prepare for the "ethical dilemna" question as it seems it is a "canned" question according to my interviewer. He did not stress too much over my goals or even why columbia. He wanted to know more about my interests and probed deepers into my answers. It probably also helped that he knew about IIT and how difficult it is to get in- so asked me about that. Overall the alum had positive things to say at the end of it and said would write a great reco (I hope he did!

). He did submit his feedback already and now am waiting for the final decision.
I just thought it was odd that CBS requires the alums to check my photo ID - nice idea but seemed odd

So be prepared to show your ID if asked!