Oh, and don't forget the other reason 777's are so much cheaper than 744's to operate: the number of business class bathrooms!

2 lavs for 49 pax on 777 (24.5 pax per lav)

5 lavs for 73 pax on 744 (14.6 pax per lav)
(plus, business passengers often overflow into the 2 first class lavs)

In terms of waiting for the bathroom, this makes a huge difference on long flights. 1 bathroom per 25 business class pax is too few.

-BP