I think he is trying to be less critical to Apple so that can remain strong if he heads off into semi-retirement etc. I imagine he will now try and groom a few people to act as an executive to be the face of Apple in a few years.
Dunno. Jobs didn't do a keynote at 2004, Schiller did, and they introduced an iMac. Last year, if I remember right, there wasn't a keynote at all and people were disappointed because nothing new was released. Except for like, .Mac or something.
May be we might have a special event a couple weeks before Paris expo and Steve might announce the new Merom MBPs plus a new iPod or iPhone or something.
BTW, it does seem that Apple is trying to do away with major product launch on events like MWSF or WWDC etc. As this will help them remain less predictable.
If there will be a keynote held by somebody else, I hope it'll be that last guy from the WWDC. He was a bit more charismatic than Phil Schiller and that French guy.