I've been writing letters to Dr. Frantz for the past few months, did the second interview thing, and he kept writing to me to tell me that I was still being strongly considered and ranked high on the waiting list (no precise ranking). I just wrote another letter last week and got a reply, and he basically said that there have been much fewer withdrawals at Columbia this year than in previous years, and unless something unexpected happens, that I will probably not be accepted off the waiting list.
Disappointing, sure, but I'm not bummed out. I got off another school's waiting list, am ecstatic to be going there, and am counting my blessings