AY has already gotten a bunch of money from Airbus as compensation for the delay in getting A350s (which AY desperately needs for its fleet rebuild). Boeing is getting record orders for the 787 in the meantime. The extra 12 inches fuselage cross-section is to catch up to the 787; it won't be like the A330/767 situation where the A330 had noticably more room and passenger comfort. The other announced design changes also seem to be matching the 787 specs rather than leapfrogging. Overall I think the A350 will be a non-event for OW, important only for the Airbus-only fleets (AY and IB).

Much more significant for OW is the 747-8; I'm sure OW will wind up with 50 more 747s over the next 15 years (effectively replacing half of the 744 fleet as it ages out).