Leonard David reports again on the X-37B/OTV vehicle: Some Details of Secretive X-37B Space Plane Revealed - SPACE.com. See the also the X-37B Orbital Test Vehicle - Graphic.
scheduled for this Wednesday, April 21st. However, there is currently a 40% chance that clouds will delay the flight: Atlas Launch Report | Mission Status Center - Spaceflight Now.
Clark's post also links to info on the Falcon HTV-2.