I'll raise a glass to his passing, for all the wrong reasons.
I went and read the wiki article on him, and though he doesn't seem awesome - I don't think I have enough information to completely understand why you think him to be a "pretty terrible person". What part of his character did you dislike?
He had other nasty traits, for instance "In the hours immediately following Senator Ted Kennedy's death, Breitbart called Kennedy a "villain", a "duplicitous bastard", a "prick"[15] and "a special pile of human excrement." But honestly, that's not really a big deal. He's entitled to his opinion, and nobody is saying he needs to be a nice guy. It's the character assassinations he performs in order to destroy political opponents (under the guise of investigative journalism) I have a problem with.