Git is good at what it was designed to do (manage and distribute changes to source code) but that's not what most people need. Non-programmers are a lot better off with simpler things like OSX Time Machine and iDisk.

That said there seems to be a lot of effort duplicated at the file-system level and at the version-control level. I hope file systems of the future will expose nicer api's (e.g. change logging) to help version-control systems become simpler and more efficient.