in my opinion, it really won't matter which OS it is. Nokia will likely NOT use the reference UI, and customize its own solution based loosely on that reference UI using the Qt UI toolkit used for both OSes.

I thought that was the entire point of buying Qt: To unify the app ecosystems and UIs of both their software platforms to remove fragmentation. You can also have UX fragmentation, but using a similarly styled UI paradigm for both OSes solves the issue.

So if this is more than just a marketing mockup (and I doubt it is...), it will likely be the basic look of BOTH OSes. The big difference will be the extended app ecosystem from MeeGo with GTK and the like.

In essence, we're all right in the end. Its NOKIA's UI. That will be how they brand/differentiate their devices, and how they unify their experience, regardless of cost or hardware.