Gents,
Forgive me for straying into the military section again....
Back in the day, did the Fleet Air Arm not have a breeding programme in which a Sea Venom would mate with a Gannet?
Definitely seen a picture somewhere of the resulting offspring (Sea Venom fuselage pod, Gannet tail assembly, "pulse jets" on wingtips, large AAMs etc.) carrying out a fast taxi run down the active runway on an Open Day...
On a more serious note, the Foxtrot Alpha forum which posted the original photo has now posted more views.
The airframe was more interesting before it was cocooned. The story was first broken by Aviation Week and Space Technology on the 13th January 2014, when they published a picture of the airframe parked beside the perimeter fence of AMARC, which is obviously where you park your new stealth test airframe.
It did appear to have non-standard nozzles, and perhaps a (partial?) Have Glass paint scheme, but doesn't appear to be the brand new aircraft suggested in the Foxtrot Alpha article.
Michael