Okay I only have tidbits on what happened, can someone explain in detail what happened?
Yogscast wanted Notch to pay them for the publicity they gave Minecraft, some kid wanted Yogscast to sign something Notch signed, they respond to the kid saying something like "We'll cross out Notch and put [censored] you" likely joking, Notch activates maximum overreaction. That's just Notch's side of the story though.
Edit: Yogscast also called them "a bunch of nerds who don't know how to run a company" which is for the most part true, at least in Notch's case.