They are using a regular filesystem on each drive and implement redundancy on top of regular files. It's more like Swift [1] than Ceph. Which is something parent should consider too, if he's going to deal with that much data.
[1] http://docs.openstack.org/developer/swift/overview_architect...
But seriously I do hate namespace collisions like this.
Swift (the storage architecture) is something i've been a fan of for years, swift (the programming language) i've dabbled in a bit and its interesting for some use cases for sure (aside from iOS programming which I'm not interested in at all). The cognitive dissonance of switching back-and-forth is annoying. I do hope nobody ever writes or needs to use a swift API connector in swift, that would be painful.