
In TV, and now in life, "jumping the shark" means that you've lost it--that you've passed, once and for all, from seriousness into ridiculousness.
And so it is with Chris Matthews. He has always been a full-of-himself pundit, who could never stop talking to let anyone else, including his guests, answer a question, but now he has descended into publicity-whoring self-parody: He is going to be a judge at the Miss America pageant.
I am not making this up. A newsman is to be a judge at a beauty pageant. Why would Matthews do this? If you have to ask, then you, yourself, aren't ready to jump the shark. But as for Matthews, you will find him deep in the salt water.
But it's still a question for NBC, parent of MSNBC, to answer: Is this really what legitimate news organizations do?