Wiki is the close as we come today. MC is changing so rapidly, that the developers would probably have to seriously slow down development if they wanted to document everything. The best thing we can do is to add what we know to the wiki, and try to help out. If there's specific questions you can't find answers to you can ask on the forums, and you'll probably end up with a detailed answer.
I do think the Music portion of MC should be pretty much the same on the two platforms.
