I am probably too optimistic about this but I think that Jolla will deliver something good. Mer and Qt are really solid base and so far hints about the UI and UX (integrating features to operating system instead of having applications around, designers being influenced by good aspects of Harmattan UI, promise to keep power users needs in mind) are promising. Also hardware is nowadays so powerfull and cheap that it should enable them to do what they want without compromises.

I just hope that they can make the closed bits good enough so that we don't need to complain about those. And open parts open enough so that community can fix them if needed.