Based on a very scientific (
) analysis of post numbers and dates, I'm guessing:
July 6, 2008 @ 11:31PM PDT (i.e. July 7, 2008 @ 2:31AM EDT)
And, since I have no life and this guess is late at night, I'm guessing that
cepheid (me!) will make the milestone post. After all, I already made the millionth UA forum post...