So I guess a round-up summary of small launcher developments in Q1 2017 is:
RocketLab have taken Electron vertical and are still promosing a launch in a few months.
Vector have created a test flight Vector-R which they intend to launch on a sub-orbital test flight soon.
Zero2infinity have ignited a [small] engine on their Bloostar vehicle.
Virgin Galactic have spunout LauncherOne development to Virgin Orbit.
Failure of SS-520-4.
Still just under 50 small launch vehicles in development, no signs of serious market consolidation yet (probably because there are also no signs of one company running away and leading the pack).