Matthew Stone runs Cumulus Networks switches in his production network. He came on the Software Gone Wild podcast recently to talk about his experiences. Cumulus, Pica8, and Big Switch are the three biggest proponents of white box switching. While Pica8 focuses on the Linux abstractions for L2/L3, Pica8 focuses more on the OpenFlow implementation, and Big Switch on leveraging white boxes to form taps and, more recently, piecing together leaf-spine fabric pods.
I believe white box switches are years away from entering campus networks. Even managed services are not close. You won’t see a Meraki-style deployment of these white box switches in closets for a while. But Stone remains optimistic and makes solid points as an implementer. My favorite part is when he describes how Cumulus has rewritten the ifupdown script, to simplify configuration for network switches (which typically are roughly 50 ports as compared to 4-port servers), and repackaged it as ifupdown2 to the Debian distribution. Have a listen.