The key thing is that the tablet UX is just a one (somewhat unfortunate) piece of the puzzle, while most of the MeeGo is developed currently in the open, the developers committing while they develop and both sources and binaries being published all the time. Also because MeeGo is actually based on the traditional userland we all know, they are working closely with upstreams. Compare this to Android's "we might release one big tarball one day of our in-house code" policy.
The thing about UX:s is that commercial needs like marketing need to have some of "wow" effect, and some companies think it's better to develop such behind the curtains. The UX:s from Intel however should eventually all be open, and they've not yet failed any promise. Even if they would fail, the whole MeeGo Core is open anyway for anyone to build and extend, and there can be any number of UX:s (like say GNOME Shell, Unity, KDE Plasma Desktop etc.). I'm eager to see KDE tablet/mobile UX:s packaged into MeeGo via for example the MeeGo Community OBS: https://build.pub.meego.com/
MeeGo has still some way to go in its openness, but they are getting there. See for example the recently opened http://build.meego.com/project/list_public view to the buildfarm. While they are doing already so well, I don't want to take the opportunity to blame them for stuff they haven't yet achieved in the openness - I really do understand there are also other objectives than opening everything up, like dealing with the potential hw manufacturers and sw developers.
I have for example done test builds of MeeGo for ARMv4 (yes, the ooold instruction set) based on current development MeeGo snapshot. The possibilities seem to me to be endless, unlike with Android where I'm discouraged that I'd need to take some random stable snapshot without any possibility to see or influence development.