from the nielsen wire:

On Monday February 9, 2009 President Barack Obama held his first prime time news conference. The conference was telecast live from 8 to 9PM on 8 networks achieving a combined 30.8 household rating with 49,455,133 viewers. The networks were ABC, CBS, FOX, NBC, Univision, CNN, Fox News Channel and MSNBC - read the rest via Nielsen.