From the BBC website:
"There are 67,000 stranded who booked directly with XL, and another 23,000 who booked via other companies. The Civil Aviation Authority(CAA) also said the firm had 200,000 advance bookings. "
Apologies if I'm being niave here, but having little knowledge of the charter/package holiday business this seems an astonishingly low number of advance bookings, even heading from summer into the winter season (and assuming the numbers are correct...)