Looks quite true, a few websites I found with that mention on google are updating at the moment, perhaps it's not true like the phony reported death of Kimo Leopoldo but there is enough consistency to think it's true at the moment.

Fmr. World Champion Boxer Murdered in Atl. - WSB News on wsbradio.com

411mania.com: Boxing - Vernon Forrest Murdered

What a friggin harsh year for Boxing.