Since we're approaching feature freeze on V2.0, I guess it's time to lay down some guidelines here.
Henceforth on app, library, or script posts
Comments
should be used for
- general feedback
- feature requests
- "bite sized" bug reports (it's down, doesn't work on XP, etc.; anything that doesn't need much context or is trivial to reproduce)
Answers
should be used for
- detailed bug reports
- comments on bug reports can serve any discussion needed to reproduce them
Edits on the Question
should be used for
- samples
- project updates
Any more detailed discussion should be taken off of Stack Apps, perhaps to an app specific chat room, mailing list, project issue tracker, or what have you.