Detail of graph showing results of study on the changing mood of pop music (WNYC)
The mood of Top 40 pop songs has turned sadder over the past 5 decades, according to a study of tempos and major/minor keys by Glenn Schellenberg, professor of psychology and music at the University of Toronto. His results are charted below by John Keefe of WNYC in New York. Blue indicates songs in minor keys; the left axis marks tempo in beats per minute. [via Studio360]
Endearing digital mashup by John D. Boswell for PBS Digital Studios.
Color-enhanced satellite photo of Hurricane Irene from NOAA (Aug 28, 2011)
The patented Map of the Market feature from SmartMoney (this view shows Aug 8, 2011) shows more than 500 stocks at once, in rectangles sized in proportion to their market capitalization, and colored green or red according to latest trading activity, up or down.
The visualization is derived from work done by Prof. Ben Shneiderman and students at the University of Maryland Human-Computer Interaction Lab on treemap displays.
From the Pew Research Center for the People & the Press, July 2011, during the budget-ceiling debate in Washington. 
This animated chart, from digital music news, shows strikingly the changing contribution of vinyl LPs, CDs and other formats to music industry profits over the past 30 years. 