[Panzerschrek]

What about filesystem access rights? Does any application have full access to all user's files? Or only to files belonging to this particular application?

[monax]

Applications will each have their own namespace, and will only have access to user files if given the right to, on a per directory/file basis

[Panzerschrek]

This is a very nice approach. You should mention it on the main page of your OS site.