This is not officially confirmed in any sense that I can tell, but Chris Mortensen just sent out this tweet:
Manning to Broncos...more coming on Espn— Chris Mortensen (@mortreport) March 19, 2012
I have heard nothing else at this point, but it sounds like at this point, the Broncos and Peyton Manning will get into the nitty-gritty details of negotiations. The rumored deal was five years, $90 million, but as far as I can tell, the Broncos seem fine with that. We'll see.
The more important question for now is what happens with Alex Smith. Do we see the 49ers kick in a few extra bucks like the Jets did for Mark Sanchez? This isn't quite the jilted girlfriend, but it certainly makes the next round of this issue a bit more interesting. This will get any subsequent dominos falling in short order. It gets a little tricky at this point so we'll keep an eye on things.
For now, "Alex Smith, please pick up the white courtesy phone."