AA seriously upgraded J meal service when they removed F from the 767-300s. It is now almost the same as IFS F meal service except: a pre-plated seafood appetizer, usually smoked salmon, marinated shrimp, plus another selection; a pre-mixed garden salad (no lobster tail or chicken or other garnish choices). The entrees are bulk packed and individually plated- a huge improvement in quality (of course a lot depends on the competence of the galley f/a on your flight!) And now sundaes in J, or fruit salad.
The improvements seem aimed at retaining the handful of full F fare paying pax and perhaps to raise the bar against some of the more service oriented trans-Atlantic carriers. It makes the mediocre J service on AA's only 3 classer- the 777, all the more obvious, especially to NRT.