I suspect that a larger issue might be that Linux users tend to run servers with multi-terabyte collections of stuff. It'd be difficult for them to make money

I suspect that a larger issue might be that Linux users tend to run servers with multi-terabyte collections of stuff. It'd be difficult for them to make money at $5 a month off a guy who wants to backup 20TB of usenet archives or whatever. Right now those kind of collections are weeded out since they don't backup network shares.