[high5ths]

I would bet Apple's never going to make this sort of a choice obvious to the user -- it goes against the "just working" (whether or not it works the way you want) they're currently pushing. It sure does worry me to read all these comments though; it seems like you'll never be able to count on an app having the data it needs to run, without re-downloading. As somebody who spends half his day in an airplane or a subway, plus plenty of time in expensive places (like overseas), that's terrifying.

[lreeves]

Actually a couple video players right now do make this choice available to the user - OPlayer and AVPlayer. They both say something to the effect of "Backup media" in their settings. This simply toggles which location the media is stored in (AVPlayer even seems to move the media on the fly).

This is literally exactly how I would implement the choice if I were Marco.

[WiseWeasel]

The problem is if the user chooses not to backup the data, it'll get wiped if she runs out of storage space. What would be nice would be to not sync to iCloud AND not get cleaned out.