[zdw]

I'm not sure that's what the earlier poster ment.

What I think they're doing (and what I've done) is add music that wasn't already in the global database to it. For example, a promotional CD, or releases from a small publisher, etc.

In these cases, you're not adding personal metadata or mixtapes.

That said, definitely do self organization if it works for you. Most of your examples seem like they're suitable for custom playlists.