@Ogi Re: I actually quite like this idea
What they are selling is a rack mountable box with these micro controllers. You would need to of course buy the switches (box == 60 micro cards, switch == 48 ports. ) Hence no need for PoE.
So not really that new or novel. They've written a FS API that support's AWS's S3 FS. While they asked about HDFS (someone at El Reg has been reading up on Big Data) but they didn't ask about actual access to the card and the underlying Linux OS or direct access to the drive.
What also wasn't asked was what happens when the drive fails?
Do they run some sort of replication and balancer behind the scenes?
Unlike a more traditional Hadoop cluster... you get to use the CPU for compute power. Although... this is most likely positioned as an iceberg storage layer.