In my 13th week now. Waiting.
As posted above, I heard back on the BW forum from Columbia adcom that 12 weeks is a guideline, but not a guarantee, and that decisions can take longer.
What's more, I'm a reapplicant. I applied last year, waited for several weeks, got an interview, which went really well, then my interviewer did not submit a report for 4 straight weeks....and when he did, I was deferred to RD, and then made to wait another 8 weeks, and then dinged. And now, as a re-app, I wait again, 13 weeks and counting. From the time I submitted my first application to Columbia, it's already been 13 months of cumulative waiting!!
As a wise person on this board said, serenity now...