The two projects that are to undergo the fairly incompetent comparison of their community development aspect are the quite humble, but unprecedented TuxGuitar application and the up and coming web player, as it styles itself, Songbird. The analysis, however, is hindered not only by the relevant estrangement of the author from the real software development process, but also by a certain lack of publicly disclosed information as the scale of both projects is not as grand as, for instance, of the most well known and discussed open source enterprises.
Now, the most notable differences of the development organization derive from the relative scale of the projects - as Songbird is, essentially, a music player with numerous extensions, features and grand customization options, its general audience is far greater than that of a quite specific and niche` product that TuxGuitar as a music notation editor inherently is, therefore the number of its contributors is significantly smaller, but their commitment to the project is much more crucial than that of developers of the former one.
Songbird does have a much better organized involvement of new contributors, be that translators, testers or developers - there's numerous sections of Songbird wiki, so to speak, dedicated to explanation of various types of contributions and ways to join the team as well as contribution score boards which introduce a game element of friendly competition, which can serve as additional motivation. Tuxguitar project administrators, however, do not make it explicitly clear how developers may chip in and what tasks are there to be done (as opposed to Songbird even having its own separate Bugzilla page). The only detected mean of joining was discovered on project's SourceForge page and is seemingly the default arrangement for all SourceForge projects. The Documentation section on TuxGuitar's site does provide some guidelines for people wishing to contribute in the translation part of the project, but involvement of new developers stops at general guidelines of importing the TuxGuitar source project.
The Songbird sports a clearly defined roadmap, frequent releases whereas due perhaps to the scale and interest rate inherent to the TuxGuitar enterprise, it is very unclear when new version is to come out and which changes it is to bring - it is, perhaps, somewhat known to the inner cycle of developers involved in the development, but it is not up anywhere for others to see and anticipate. Even great deficiencies, such as the inability to handle the newly issued of GuitarPro format (TuxGuitar was also conceived as a free alternative to GuitarPro, which would enable editing of files in GP's native format) are not fixed for many months and no announcements are made on the progress of conversion and deciphering.
Moreover, Songbird has it's own "infrastructure" for downloads, source code hosting, various guides and API documents meant to make developers' tasks easier, better diversify them and provide sufficient explanations and manuals so as to make the involvement threshold lower, TuxGuitar, however, heavily relies on the infrastructure provided by SourceForge and is very lacking in the explicit and sophisticated guidelines department. Furthermore, TuxGuitar doesn't really have - or need, for that matter - an add-on system which is also contributing to the influx of developer power into the Songbird project.
Songbird, though indeed having known bugs that need fixing, having planned enhancements of functionality and such, is past the era where practically any brain could provide invaluable input - the added functionality is more and more complex and most apparent, highly needed add-ons have already been written and coming up - and being able to realize - with something new and desired by the public does indeed require one to be quite imaginative and inventive.TuxGuitar, on the other hand, is more challenging in its entity as being relatively unique enterprise with much fewer actual open source predecessors where inspiration, ideas and approaches could be taken from. Sadly, it being a very niche product prevents the very much needed inflow of quality developer material.
As it would seem, both projects financially survive on donations of the audience and, in a minor way in case of TuxGuitar, on providing advertising space.