tedster - 3:42 pm on Nov 1, 2010 (gmt 0)
Where did that traffic go?
If you read the Alexa blog article, they state the obvious - search is nearly a zero-sum game and the traffic went to other sites. They even include a graph of one such site with a huge up spike.
This is Google's "holiday shopping" algorithm. You'll see another big change after January, and they certainly will continue tweaking between now and then.