...Well, if it was a joke, it sure flew over my head. It didn't sound like a joke at all.
Here is the excerpt which I refer to. It is paraphrased, of course.
Jimmy: "You know, Ben, if you told me back when the show started in 1984 that we'd still be on in 2000, I would've said you were crazy, but here we are."
Forgive me, but this doesn't strike me as a joke. If it is, feel free to Whoosh the living hell out of me.