Congratulations to everyone who has worked so hard to make Gnome 3.0 a reality. It’s a great accomplishment, excellent work by many people, and worthy of celebration. I know the PPA is popular and I’m sure it will be a hit in 11.10. Well done all!
Now at the moment it seems, even though a PPA exists for installing Gnome3 in Ubuntu but it is unstable and even the developers warn about it easily being able to break your OS. PPA stands for personal package archive, so it seems that, Canonical has no intentions whatsoever to officially support Gnome3... they are relying on the PPA developers to do that for the users. Although, they will have come into the picture since Gnome3 or the Gnome Shell is not compatible with the Ubuntu Unity (at least at the moment) and they are the experts of Unity Desktop.
Unless the Ubuntu community stand-up and says "we want Gnome3 officially supported!" I don't think Mark or Canonical has any intentions to support it. I may be wrong here... what do you think?.