On Alexa.org, try the Traffic rankings, comparing WP with the BBC site bbc.co.uk, and looking at the Page Views tab: like
http://www.alexa.com/data/details/traffic_details?&range=3m&size=lar... .
Then since Christmas WP and the Beeb are almost spookily tracking each other; and not just in the weekday/weekend fluctuations.
Any idea of what this might mean? The numbers could be broken; or the demographics match amazingly over the population from which these things are calculated.
It could mean that WP became a household word in December; in that target group.
One to watch.
Charles