1) Merge resolution is a big one. I often muse that a note-taking app with a Git backend and three-way merge facility would be kind of awesome.

2) Combine that with offline note taking that auto-syncs when you have a network connection again (even if the note-taking app is backgrounded on your phone), and you'd have a winner. Give me that and I wouldn't even care about support for any formats other than plain text.

3) The ability to organize notes into folders and subfolders with no limit to levels of nesting.

OK, yeah, I really just want an auto-syncing Git client on my phone.