Wow I had no idea that caffiene was more potent when you quit smoking... Hmmm, that makes sense..
Anyway I quit smoking on new years of 2009 and I'll admit I've gained some weight since. And I'll give the strong sweet tooth I've gotten credit to that. I also agree thats its a huge oral fixation. I've also started chewing my nails. And I eat a lot of hard candy. But I think these things are better for me than smoking.
I haven't had problems with sleep though. Although when I do wake up I am starving and have to eat right away, when I smoked I would have a cig right away and not eat for hours. I can actually say quitting smoking was easier for me than quitting my pain pill addiction. And I don't mind the extra weight too much.
How long have you been smoke free? Good job quitting!

I hope it sticks for all of us who have quit..
I don't have any other info or advice on this, but good luck