I was faced with the exact same decision (ie, whether to go to Yale or Columbia for PNP). After attending Columbia's visiting day this past Friday, my "gut" feeling was confirmed about Yale being the better option. I was not overly impressed with Columbia on visiting day for a number of reasons. For one, I cannot seem to understand how they justify charging significantly more in tuition than other comparable schools (like Yale) when no aspect of the school that I have seen (ie, the facilities, administration, etc.) seems to be superior in any way. Attending visiting day also confirmed a notion I had heard from several different sources about Columbia's administration being often disorganized and just plain difficult. I don't know about you guys, but I'm not about to shell out a ton of money for a grad program in which I will be treated poorly in any way. When I asked a number of current students if they could name one or two "negatives" of the program, their answers consistently pointed to a lack of both friendliness and organization on the administrative side of things. Even with a tremendous faculty, having poor administration can make life unnecessarily difficult and that is something I'd like to avoid at all costs.
This morning, I drove up to Yale (my parents live in CT) for one last look around, despite the fact that I knew the school would be closed on a Saturday. Serendipitously, I ran into a current student (also in the peds specialty) who couldn't have been more kind in her demeanor and positive in her overall impression of the program. The fact that this was a random encounter (and that she wasn't someone chosen specifically by Yale to speak to prospective students on interview day) really cemented in my mind the strength of Yale's program. Not to mention the fact that I feel that Yale is just a great place to be for those in the peds specialty. On interview day, it was noted that much of the school's leadership has a background in pediatrics, and yes, Yale does have the #1 ranking for PNP in the country from US News (for what it's worth).
One last thing I've been reminded of over the past few days is that everyone is looking for something different in a school and is entitled to their own opinion. I spoke with a current Columbia student at visiting day who had gone to Yale to interview last year and came away with a very negative perception of the school, citing the fact that she was unimpressed with both her faculty interviewer and with Yale's location in New Haven. Granted, I'll be the first to admit that New Haven is no NYC -- but to me, it's more about going to a school with a strong program, faculty, and student body. In my experience, Yale has consistently proven to be top notch in all of these aspects, and so that's where I'll be in the fall. I wish everyone the best of luck, wherever you end up!