What Agile principals can be extended to classical volunteer Open Source Project Management?
Challenges compared to a traditional workspace.
Managing burnout / over-commitment of volunteers.
Enforcing accountability, without shaming or otherwise making organization members (or outside contributors) feeling isolated or abandoned.
Getting accurate estimates for releases, how to deal with deadlines without a consistent base workforce.
Handling the public / users who are demanding, because being 'whiny' often gets them the attention they need, at the risk of long-term dev burnout.
Keeping interest in your project / community by developers (rather then users)
I think you would be able to do scoping, and estimation pretty easily, you could track velocity, which could help point out signs to burnout early, as opposed to meeting a future release (keeping the 'when it's done it's done' attitude).