This looks to me like a great little partnership. One thing that's always bothered me about Maemo as a project is that it is largely only for the devices of one company. Merging with Moblin and handing it over to the Linux Foundation cures that concern.

It also creates a pretty sturdy competitor to Android - and a more community-focused one at that. I've never liked Googles 'each-release-over-the-wall' approach to open source - the Meamo (and Moblin, AFAIK) approach is much more cohesive (though it bothers me a little that there was little/no community input on this merger).

As for Maemo 5 - from where I'm standing there's nothing 'Beta' about it. Does everything I want it to, and it's nice and open like I'm used to on my desktop.