Randall Munroe, the young and famous author of the xkcd webcomic, has just released a beautiful knowledge visualization. It’s the update of its online communities map. “Size on map represents volume of daily social activity”. The map is very well done showing both how the map is embedded into a bigger context (spoken language, email, sms, etc.) and providing as well zoom-in for the two hot topics of blogs and forums.
It’s a nice mix of informative content, providing overview and details, and hilarious jokes of the Web 2.0 mania, such as “desert of food updates” on twitter, “people you can’t unfriend“, and “the great firewall” between China and the rest of the map!
Sabrina Bresciani, Ph.D. 
Love this!!