Developer's forum section
How about adding a forum section here for development questions/discussions?
I create some new Forums for development.

But, my first question would be, which kind of discussion do we start here, and which kind of discussion do we start on GitHub, or in general, does it make sense to have developer discussion here on the forums?
I was thinking general questions that doesn't suite a GitHub issue, like "how would I go about adding a format" or "what are the requirements for the (...) function". General questions like that.

Forums may also be better for discussing broader issues like "should we make the OpenCL kernels device agnostic, and how?" or "should we try to support OS X at all? What are the caveats?".
Fuck off with OSX. Have a nice day.
True, writing such an article about how to add new formats is something that many people could interesst. That _does_ make sense, Xan!

For OSX I think yeah we should, but I have no clue how to do it. Also I didn't own a Mac so I couldn't even test it.
Right now there's no point even trying. OSX' current OpenCL drivers are literally unusable, they're like 25x worse than AMD's. Before El Capitan they were perfectly fine.