Flightdata show that they flew for more than 6hrs. Never flown the 737NG, but that must be pretty close to max endurance not? Would they still have the fuel to divert?
Given the "light pax load (thank god for that one) and a low fuel load, the aircraft must have been very light. This together with a dark stormy night (likely IMC), would have been the perfect scenario to create visual illusions in the G/A... Look up GulfAir in BAH, Afriqiyah in Tripoli, B737 in Kazan...
I know it is too early to speculate, but feel awfully close to the Kazan B737 crash!