I don't think this can be seen as a possible replacement for PC disk because of it's high latency. Beside unless you are very rich Ethernet is only 1Gbit/s.
On the oher hand I see an opportunity as shared storage for mobile and ligthweight devices. Using a single and simple protocol, compared to NAS, could open a new technology domain and market. Of course it requires also a good integrated authentication and access control system because on Ethernet this data might be open to the world.