From a friend on the "inside"…
You're right that [Letterman's] not dancing a jig that Leno's going off next February. It puts the spotlight on him to now begin making a graceful exit or justify why he's staying on and not letting CBS which has been so good to him, begin breaking in a new and younger host. Also I don't think this is likely but what if he starts getting clobbered by the two Jimmys and has to go out in third place? He'll wish he'd left when Jay did.
Leno going off means Dave will never have the triumph of finally beating Leno once again. No one thought that was ever that likely but it was also far from impossible. Jay hasn't been beating him by that much.
As you said, Dave doesn't have anything professionally he wants to do after he leaves his current show. He likes appearing in front of an audience as long as every single aspect of the appearance is under his control. He's God up on that stage for an hour a night and that's the only way he's happy. I always thought he envied Leno's ability to go anywhere and be happy entertaining any audience on any stage. His big trouble with retirement is that he loves that office and that building and having a staff and being able to get away from his house for the day. To have all that, he needs to have a show.
[Les] Moonves remaining in charge at CBS is a pretty safe assumption but I'm not sure Dave can stay on as long as he wants. That was the deal for him being as cooperative as he's been all those years there. He must have a certain sympathy for Leno who was promised all sorts of things by NBC and then different men in suits came by and reneged on what their predecessors had promised. One of these days though even Moonves may have to tell him nicely it's time to start on an exit strategy.
I agree with you his replacement won't be Ferguson. Everyone seems to be saying it should be Colbert. That means it won't be. I read someone say NBC might try and grab Colbert for Fallon's old slot. That will never happen. I'm not sure it will be Seth Meyers but it will definitely be someone who owes their career to Lorne. Lorne doesn't like the whole idea of anyone achieving comedy stardom without owing their career to him and Colbert is already a star without that.
re: Leno on Fox. You're right it's possible but not likely. The argument for it is that if they're ever going to open up that time slot for a talk show, this is the only chance they'll ever have to launch it with someone with a 20 yr. track record of success in that area. The argument against is that it's an investment of years and years in a guy in his sixties and it means dumping the reruns that are working well as counterprogramming. Our mutual friend [name redacted] thinks that it would be a bad marriage because Leno would want to do jokes in his monologue slamming Republicans and positions that Rupert Murdoch is pushing. He'll overlook that from Bart Simpson but not from Leno.
We agree on Kimmel whose show is awful. He's the penalty that Dave and Jay are paying for letting their shows get so predictable and formula. There was room in that time slot for anyone with a whole new act. Fallon will do better than Kimmel for the same reason Leno did better than Letterman. Bedtime is an hour to spend with people you like and people just like Fallon a lot more than Kimmel.
I don't know about Conan. He's got to be wondering what would have happened if he'd taken the offer to do Tonight after a half hour of Leno. The main reason he said no was that he and his people were sure Leno would never leave again until they carried him out feet first.
I don't think they would have considered putting Conan back to 11:35. The most likely result of him being moved to 12:05 would have been being bumped later back to 12:35 or fired with a less lucrative settlement than he got…and then having less "heat" when he went looking for his next job. Fox was interested in him when he was the guy who walked off The Tonight Show and even then, they couldn't put that deal together. They'd have been a lot less interested in him after he'd been fired or demoted from that later slot.
It's impossible to predict what Leno will do, especially since we have no idea when he'll be contractually free to negotiate with suitors. That probably means he doesn't know and is waiting to see what kinds of offers he gets. Well, actually, we can predict one thing with great certainty: An awful lot of well-compensated stand-up bookings. That's what he always does when he has free time.