Please see the most recent updates in the "Where did the .com name go?" thread. Posts number 16 and 17.
I think you are right, you can see the reflection of the horizon along the fuselage and left wing. Still a cool shot though.Is it just me, or is that photo titled ninety degrees to the left? The clouds on the left side of the shot looks a bit odd. To me it seems this F-16 was making a high-G low level turn at a ninety degree angle and the photographer snapped this shot from behind the aircraft.