This is what it should have been doing all along but at least now it’s here.
When restoring data, all app data is saved. I don’t want to assume anything but I’m hoping it means things like game data or whatever content you have within the app just saves.
What’s more is that it doesn’t affect your storage. It’s an automatic one day thing (I’m not sure if there is a manual option to save).
Tiles are also restored. Although I welcomed the backup system in WP8, I didn’t like having to edit my homescreen again. Well, in a way it was kinda fun deciding where things could go again but that’s not the point.
Source: Justin Angel