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WhiteKnghtTwo, the twin-fuselage carrier aircraft that will lift Virgin Galactic's suborbital SpaceShipTwo to its 50,000ft (15,150m) launch altitude, is......

Author: Rob Coppinger

Date: 06 February 2009

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 Those look like "wool tufts" used to indicate local flow and flow separation, not vortex generators.

 You can just about make out the vortex generators ahead of the rudders. They go from the level of the elevators down to the bottom of the fins. Look at the 'i' in the Virgin logo.

 Hmmm.... could be at that.

Note for future photos of this ilk - zoom in a bit or circle the items of interest. At the resolution on my screen for that photo size (plus my 50+ years-old eyes) it's difficult to make out just what those small gray items might be might be.

Cheers!