There is the data, and there is the understanding. Somewhere in the middle, the communication. Also visual. See a list of current visualizations of the WikiLeaks Cable Gate data below.
. The Guardian - US embassy cables: browse the database
. Der Spiegel - "The US Embassy Dispatches Interactive Atlas"
. WikiLeaks - "Graphics of the cablegate dataset" (scroll to bottom, created with Tableau Public)
. The New York Times - "Letters between Wikileaks and the U.S. Government" (not really visualizations)(yet?)
- The Guardian - "Where are the Wikileaks Cables From?"
. El Pais - "El intercambio de documentos y las zonas calientes del planeta"
. Jef Thorp - " Exploratory Visualization of the Wikileaks #cablegate data"
Please add more sources in the comments!