H/T to Charlie
I went back through the author's methodology and didn't like the way he extrapolated the numbers. I went through the government's stats (FBI Uniform Crime Reports) for 2011 and 2012 myself and came up with a lower number: 8,663. Using the 2011 FBI numbers (the 2012 report will not be ready for months) blacks were responsible for 14% of white murder victims while whites were responsible for 7% of black murder victims.
Therefore it is not unreasonable to pose the following: blacks are kiling whites twice as much as whites are killing blacks. This is based on HARD DATA from the FBI's 2011 Expanded Homicide Data Table #1 found at this url.
There are problems (there always are) in the FBI's Expanded Homicide data. It only includes those murders where the age, sex and race of the offender is known. While blacks comprise 13% of the US population (40.25 million out of 308.74 million), black murder victims comprise 50% of all 2011 murder victims (12,664 where the age, sex and race of the victim is reported - there were actually 14,612 murders in 2011) and 91% of blacks (again this is hard data) are murdered by blacks. It is very likely that the ratio is more along the lines of 3X more likely rather than 2X.