My guess is that all 762s will be gone by the end of summer. AA plans to have them "decommissioned" by June. But US seems to have them doing extra summer service (although fewer flights next summer than this past one-- so apparently some will be retired by then). However, that could still change now that AA's 763s are part of the mix. I suspect the 734s are in their sunset years. I don't think they will be ringing in the 2015 New Year at US. And US's 752s? That's a good one. They only have about two dozen of them. But they do use the same RR engines as AA. The only difference is the door configurations. I actually prefer US's for transatlantic flights (in Y) because of the lavatories at the 3 L/R doors, and not near the back galley. It makes it easier for FAs and Pax IMO.