What problem is mediagoblin actually trying to solve? Is it organizing your media or is it being a new social network? Because one of those makes sense and one of them does not.
> So, if you create content with a...
Mediagoblin isn't for creating anything, and it certainly isn't a network client. It is (ugh, should be) a tool for organizing your media.
Know what's a really great technology for sharing media? Hyperlinks. We built a visual web that is literally world-wide using them. Know what people don't have any trouble sharing media to using hyperlinks already? All of their social networks. Know what hyperlinks don't need? Years of effort spent chasing a white whale.
Mediagoblin still has a chance to be OpenFlickr if they would just stop faffing about with things that don't have any connection to it and start focusing on core competencies and important things like installability.