John Gruber at Daring Fireball links to an Amazon announcement that comes as close as Amazon has ever come to actually revealing how many Kindles they have sold:

"...in just the first 73 days of this holiday quarter, we've already sold millions of our all-new Kindles..."

Amazon still won't talk numbers, but this announcement—which is relatively hidden in a forum, and not issued via press release—is obviously impressive. They've never been so specific before; if the Kindle sales numbers hold up through Christmas, I'd expect an actual announcement from Amazon in the new year.