One in 10 communications companies claim to have deployed 5G technology already, according to a recent survey (see: With 5G technology, the time is now).
Some parts of the 5G standard are close to being finalized, but nothing has been ratified yet.
Furthermore, many of the constituent technologies (e.g., mmWave RF, beamforming, MIMO, etc.) are either new or not commonly used. SDN and NFV are considered critical enablers of the heightened utility and expanded flexibility that will be hallmarks of 5G networks.