@Otto - Yes, there is that downside to GitHub forking so that probably wouldn't be appropriate for WordPress.org where there is already a large amount of plugins with similar/crossover functionality - being able to easily fork these may just lead to even more confusion and overlap.

What about the idea of standardising the use of some tags like "seeking-committer" or something so that authors could 'advertise' in some way that they are looking for help with a plugin.

I know that this would not necessarily be a sure way to eliminate orphaned plugins as it would still rely on an author adding this tag, but it may provide a way to promote more collaboration among plugin developers? I guess we could just start doing it and see if it takes off and standardise it if it seems to become used.

Could also use tags like "seeking-translator" etc