Some folks are writing to congratulate me on my seeming prescience. It's because of this story in which the New York Daily News says that David Letterman's show is pulling out all stops to get Jay Leno on as a guest. Let us note that the Daily News has a pretty lousy track record for accuracy. Let us also note that this is a pretty easy prediction to make.
The last time Leno left The Tonight Show, Letterman's folks wanted him on. In fact, they wanted him on the same night Conan O'Brien debuted to try and steal the spotlight that evening. Jay declined because he thought it would look like he was knifing Conan, little suspecting he'd be accused of that no matter what he did. He's probably wondering right now how long to wait before he goes on with Dave so it doesn't look like he's undercutting Fallon. He's probably also wondering where and when to make his first advertised guest appearance since leaving The Tonight Show and whether Dave's show is the right place to make it. I'm curious to see what he will decide.