The people in the black shirts in the middle are the New Horizons principle investigators. This is about 10 minutes before closest approach, as reported by the "live computer simulation" on the projection screen. The guy on the right with white hair and two flags has been involved in the probes to every single planet (and now former planet) in the solar system.

Taken with my phone (MEH) at the Kossiakoff center at Johns Hopkins Applied Physics Lab.