If MeeGo-Harmattan is really expected to be mainstream (not just another beta step), then Nokia should be asking themselves about the benefit of Extras being enabled.

I suspect the most immediate benefit is having a large amount of apps available very quickly after launch. I also suspect that community resources may be quickly overwhelmed by testing requirements. Particularly in the case of few devices being available for testing prior to launch, or a slow to start developer program.

So, I would suggest that it would be in Nokias best interest to have a couple (or more) paid tester positions prior to launch and for sometime afterward to help the community test and promote quality apps quickly.

If that isn't economically feasible (beneficial), perhaps Nokia could implement a programmers discount system. Reduced cost / streamlined access to a "free" section in the Ovi store for programmers that have shown to be contributing to the community. Make it easy for these folks to get stuff submitted to the Ovi store. Ovi QA would be in place, and Nokia would benefit from having the apps in its store.

I think in the case of a mainstream device, the majority of apps should come from a "sponsored store", not a community supported repo. This would significantly reduce stress on the community. I think most mainstream users would blame Nokia for problems perhaps related to mis-behaving apps anyway, so Nokia should have some control over them.

Extras should contain stuff that Nokia couldn't/shoudn't support in their store (enhanced kernels, emulators, Chromium, etc). In this case, Extras should not be enabled by default, and only enabled with whatever warnings are warranted.

Just my thoughts.