Fedex has optioned the A380 as well as operating a large amount of A300 and A310 freightors.
UPS has twice ordered the A300 for 30 and 60 planes respectively- with options for LOTS more.
UPS- also has options in their contract to convert A300s to A380s.
Atlas is likely or was likely to order the A380.
It is likely that at least one or two US domestic passenger airlines will use the type.
It might have been a A300 cross the pond, then a 757 or 767 to SJC, because I've seen a sight that says one of the LHR-BOS flights goes on to SJC. AA has a big base at BOS, and they might use the original A300 on the turnaround route to LHR or to SJU or MIA.
A lot of the JFK-SJU flights are on A300's as well as to other caribbean destinations like Santo Domingo and other Latin American destinations . Other than US Airways and NW I dont see any other US airline ordering the A330 . Most probably when AA replaces the A300 it will most probably be with Boeing equipment .
There are only 3 routes operated by widebody AA aircraft out of SJC. SJC-NRT, SJC-CDG (4/01) and SJC-TPE (4/01) all operated my 777-200 aircraft. All other flights are operated by 752, 738 and MD80 aircraft.