I've had the same thought many times, when some radio jock announces that he's got an, 'earth shattering revelation' that he's gonna release in the near future.
Glenn Beck ruined his reputation with most conservatives by playing that trick too many times to count.
I get ya.
Thing is, this is the very first time I've ever heard Mark Levin allude to being in possession of some kind of game changing information, and I've been a listener of his show for a very long time. Mark just does not play that sort of bait and switch with his listeners.
My guess is that he has something that either doesn't have all the loose ends quite tied together, or he's got to wait until his legal foundation makes some sort of filing prior to his revealing it. Frankly, he probably wishes he hadn't mentioned it until it was ready for release.
You’re right, he shouldn’t have mentioned it. I’ll “give him a pass” on this (in terms of my own opinion) ... if this is not something he does and it was a one-time slip-up.