As a network guy, it's a _great_ time to be an experienced network person. The only mature aspect of the ill-defined SDN sphere is OpenFlow and that will only get you so far. Try as they might, controllers like OpenDayLight and the various things that plug into Neutron/OpenStack aren't plug and play for those w/o significant network knowledge.

From my vantage point, it's going to be at least another five years before the cost structure really does turn over on it's head for folks below the hyperscale level