I wouldn't put *too* much stock in the facebook group as an accurate determinant, for two reasons: not everyone is on facebook, or in the group. Shocker, I know, but I know several people admitted but not in the group.
Second, there are a bunch of deferred students (such as myself), some of whom are in the group, thus inflating the total number of 2010-2011 "admits". Whether or not these two groups cancel each other out numbers-wise is debatable.
That said, based on my past two years watching the group, the deluge is very nearly upon us. It usually goes from <100 to >200 in about a month; indeed, it was <70 until this past week.