git notes primer?

Hi,

I'm working on a patch management system as topgit, but without the complexity: http://koch.ro/blog/index.php?/archives/139-tnt-is-not-topgit.html

Before I continue with my current design, I wanted to have a look at git notes, whether it would provide better mechanisms then tracking my meta informations in a hidden background branch. (Much like pristine-tar does.)

However I couldn't get a grip on git notes:

- Is git notes the only command that works on notes?
- How are notes saved inside GIT?
- Is git notes and it's implementation stable now?
- Are there any tutorials on workflows with git notes?
- What different use cases of git notes do you know?
- What use cases triggered the development of git notes in the first place?

Thank you for your time,

Thomas Koch, http://www.koch.ro