Last year (on SDN) the bulk of reference calls started Wed-Fri the week prior to decisions - so Jan 20-22 for the Jan 29 release last year. We're past Wednesday and with a larger pool of applicants, I think even next Friday will be a stretch unless they start calling in earnest tomorrow. I do think that references being called will be a good indicator that it's getting close though!
They did tell us we would hear mid-late Feb, so even Feb 10 or 17 is on the early end of what they indicated, though I know that's not fun to hear. I do hope that it's earlier, but I bet they are beat with such a large applicant pool and being down an admissions staff member (I'm sure they are working hard and probably about as ready as we are to have it over, lol).
Regardless, we shouldn't have more than a few weeks more to wait!
(PS for the question asked: my references have not been called and would most definitely let me know)