This showed-up as a link on one of the motorcycle forums that I frequent and it is probably of as much interest to cycling advocates / facilities designers as it is to motorcyclists. What you’re seeing is a composite view of “road fatalities” that have occurred between 2001 and 2009 in the United States. You can access this map by using the following link: http://map.itoworld.com/road-casualties-usa#
Cyclists are color-coded Green and if you zoom-in closely enough, you will see that each icon includes the age of the decedent, the year they were killed and their gender, e.g, note that a 34-year old male was killed in 2005 at an extremely busy intersection where some 16 different lanes converge to send road users to Costco and several other shopping centers, with very large gas stations on opposite corners of the intersection.
Note that ITO is a UK-based company and, as you might expect, the data they have for the UK is far more extensive.