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I am using G2X since 2006 and I have been more or less "online" on those sites. Trying to find informations, docs, modules in two sites is hard. See the large number of newcomers that do not know where to read first ?? on codex ? or to put a question on forum ? My suggestion would be to simplify them and unify them: not all the visitors are proffesional developers, not all of them are advanced users/installers.
As for the community of developers, my suggestion would to put a space(only one) for everybody to upload/list their modules/mods/hacks. And promote them! After all, if you focus on the core of the Gallery and coordination of developers, you can achieve more!
Just my thought, if you don't like, ignore!
I see the future of gallery as a media management platform, which consists of a minimal core (more like the platform/framework) with easily plug-able modules for everything you migh want. (easily plugable module means something like Joomla's upload zip and install) example: REORDER/REARRANGE - independent modules; someone uses REORDER, someone uses REARRANGE - but the platform allows!