Nokia currently is not prepared to waste resources opening further Maemo components (though this may change). We, as a community, have pretty much zero influence on this though, and any change is likely to come about due to MeeGo rather than explicitly for Maemo.

Some drivers will get released as part of MeeGo, possibly all of them - the MeeGo web site/forums/mailing lists would be the place to find about this though. I foresee very little chance of getting the entirety of Fremantle open sourced though, and absolutely zip the community (as a whole) can do about this.

My current expectations are for Maemo 5 to hold out at least until the MeeGo release (it's still doing everything I need in a phone, and my issues with it are very minor), then I'll be weighing up the options of either a community-supported MeeGo release for the N900, a new phone, or sticking with Maemo 5.