It's not racist. It's a criticism of BET and Robert Johnson. Dunno how it's particularly relevant here, other than for the shock he's trying to elicit. But his post isn't racist. If anything, BET is.
There, I probably started some ****, so we got a nice west mall topic. GO!
I take it as commentary on the fact that Bob Johnson tried to smear Obama with the statement that:
“Barack Obama was doing something in the neighborhood – and I won’t say what he was doing, but he said it in the book"
which implies Obama was using or selling drugs. Yet Johnson made a fortune off media that often glamorously portrays the lifestyle associated with what he was condemning.