I did not think much of this the first time viewing, but an Object Report operative wrote in and suggested it could be a V-shaped craft as seen from the side view, so I'm taking a closer look. 

Watching the video at .25 speed using the YouTube slow-mo option under the gear icon, I did notice the object appears to be blocked by the aircraft tail - this would put the object far away from the video camera, eliminating the bug, dust, artifact possibility. 

The object also appears to lengthen and shorten as it moves, which would point to a V-shaped or boomerang configuration, rotating about its Y axis. This video is very short, it is very blurry and the object appears to be moving in a similar, upward angle trajectory as the Virgin aircraft - which would suggest another aircraft simply taking off and climbing from this airport or one nearby. However, the object is moving quite fast, which of course would suggest it is a fighter or small private jet but these sorts of speeds are not usually granted in controlled ATC airspace, but not impossible and its difficult to say exactly how fast this craft is moving - but to me it looks too fast for a normal takeoff departure. We still are left with the strange contraction and extension factor of the object as it moves across screen and the general shape, although very blurry, does not reveal a vertical tail stabilizer and we have no blinking lights. 

Agent D
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