Ooooh! The mashup geniuses at Faneuil Media have put together an elaborate map of New York murders to accompany this New York Times article. The data spans the last three years. Some people have reported the mashup is loading a little bit slow, so if its not working for you, check out this static map that the Times through in for good measure:
The bottom line: murders are concentrated in poor neighborhoods, especially in northern Manhattan, Eastern Brooklyn and Queens, and the South Bronx. If you look at the data, Blacks and Hispanics make up 89% of murderers and 87% of victims, and almost 90% of both groups are men. Some mild surprises: almost 70% of the victims knew their murderer, and while guns accounted for 66% of the murder weapons, "cutting" instruments were used 22% of the time.