Ubuntu is Debian. It's just debian modified, more-so than most phones will be from MeeGo. It would be like, if Ubuntu used debian's own repo's and just setup sudo-packages to pre-install certain configurations. That is how I see MeeGo operating. The MeeGo we get from phone to phone is likely to have a very different user experience. Somewhat like the HTC Sense UI vs MotoBlur vs ... the Nook. And some (or most) of those experiences can and likely will be very proprietary and unable to screw with.
Just because MeeGo goes the way of, say, pulseaudio or alsa or whatever, doesn't mean the end phone based on MeeGo needs to.
They can have their own proprietary system in there if they want. Our current issue in Maemo with the audio system is it's not documented, and the core media apps are closed right? Nothing is stopping Nokia from doing this all over again with their phone based on MeeGo. MeeGo is just the basic OS.. everything on top of that will be up to the discretion of the manufacturer. Unless you're telling me that the Linux Foundation is going to start requiring people using MeeGo to abide by certain rules to using their OS....
Versus.. what? The continuing downward trend toward failure, like now? If Nokia produced Android phones in addition to MeeGo, they would at least be competing and making sure their brand was relevant. SELL THE CUSTOMERS WHAT THEY WANT. Is that really so hard to understand?