What AA HAS invested in which many other airlines haven't is powerports. They're available on all (or virtually all) planes, throughout the cabin. Not all coach seats have access, but many (most) do. Can't say near the same thing for Delta.
It was absolutely painful making it from BCN-ATL (nearly 11 hours) last year in Y without a powerport. One movie was all I could watch on my laptop (in fairness, my battery is not great) and that was it. DL has no PTVs on their 763s, which are what make up the backbone of their TATL fleet. Ironic that so many of their domestic flights have them but only a few of their international (and yes, I know it is a weight thing, but still...).