So the problem Drew mentioned, of mapping between different sets of sync folders on different machines, is transformed into mapping an identical folder hierarchy (i.e. the dropbox folder and contents) to arbitrary sync files/folders, done by the user, for that specific machine.

You get the simple, instant user model (dropbox folder), which you can customize to any arbitrary user model, as much or as little as you want, when you want it. And simple syncing.

I just keep my config files in git. Having to commit changes is a good thing, not a nuisance - being able to track changes is hugely useful.