price/value
Unless rack space is at a premium, customers would find more value in simply buying an ethernet switch and a fibre channel switch separately. And with fibre channel, switches are almost always deployed in pairs, so there is limited value to convergence.
This little switch might be just the thing for a remote node (say, a disaster recovery setup) in a distant colocation facility somewhere. One of these, a decent filer, and a box full of KVM or VMware blades, and you've got a data center in a can ready to handle your DR needs.
Still, with 10 Gbps Ethernet now affordable and NFS handily outperforming Fibre Channel (NetApp for the win!) I see little value in deploying dual media at this scale.