One side that's probably not considered often here is that even though Nokia is using open source software the business processes might not be as open and so hence the delay.
Concerning updates on included software, the questions that have to be asked include: - does the update address something that has no dependency on locale/carrier included parameters with an object? If it has a dependency, how can Nokia communicate their process effectively without damaging stakeholder relationships? - Maemo as a commnuity needs to help enable Nokia to be able ot answer this question.