Here's a link to Bill Carter's article about the Leno/Fallon transition. It's Mr. Carter's station in life to accept and pass on whatever the main players in the Late Night world tell him (at least until he writes a book) so he makes the whole thing sound like a big love affair with everyone getting what they wanted. I think it's safe to assume Jay Leno is not happy with any part of this except maybe that he doesn't look quite as "fired" as he did last time they tried this.
In the Carter piece, Jay makes it sound like he has no offers and may not go back into the arena. I've heard from several sources that he has and will be getting several offers, some perhaps quite enticing. Whether he'll grab any of them, even he doesn't probably know yet. I'm sure he could be quite happy the rest of his life doing stand-up and various guest appearances. One wonders if Letterman's show will be among them. In Carter's last book, he said that Jay was asked to guest with Dave on the night that Conan O'Brien took over The Tonight Show but that he declined the offer, feeling that it would be a slap at Conan. He certainly won't go on opposite Fallon's debut but — assuming he hasn't already announced a new competing show by then — he'll probably get an invite to drop by at some point.