If It Bleeds, It Leads -- If It Enrages, It Engages

Old media wisdom, updated for the new media.

I heard the second half for the first time yesterday, but the earliest reference I could find online is from commenter En Passant at Popehat, in a comment to a post about Nancy Grace:

So Grace's behavior furthers her business. If it bleeds, it leads. If it enrages, it engages. If the jury acquits, you have a fit. Savaging the victim may be rank, but you can take it to the bank.