That's what I thought it was, too, at first glance. It would be some gnarly math to figure out how to make the storage reliable, since clients could arbitrarily connect and disconnect at any time (carrying a portion of your data with it). I suppose it would be an algorithm similar to RAID, except that there would be an algorithm that would detect damage, such as not enough backups online for a certain time, and the risk the data would no longer be available, and then in response create another RAID node.

Bandwidth could be an issue, too. Maybe clients could get bandwidth and storage karma, if they accept a lot of data from other users and a lot of changes to that data.

Interesting idea, anyway.

Edit: maybe you could even sell your processing power for karma, too. And maybe even extract that karma to sell/trade/give to others.