As I write, we're flying from New York JFK International Airport to Madrid Barajas International Airport (MAD) aboard an American Airlines Boeing 767-300, the smaller of the Boeing wide body long airplanes. We're spending this leg of the journey in Economy Class, so we're able to offer worthwhile tips to anyone flying similar American routes on this plane.
JFK is, of course, American's primary European gateway hub, while Madrid -- as the capital and largest city in Spain -- is a major throughway on the other side. If you're booking with American AAdvantage miles, be mindful of the possibility you might find yourself in an inconvenient (to say the least) situation where you're flying into New York at LaGuardia Airport (LGA), and then hustling across Queens to get to JFK. Once there, you'll find that American's Terminal 8 is bright and clean, with bit open spaces and an Admirals Club lounge in the far concourse that is among the better we've visited.
Airplane Look and Feel
The plane itself is updated to what we'll call quasi-modernized. Some elements of the hard product seem more fresh than others. For example, the seats are firm and new feeling, but the interior walls and windows have a distinctly 90s look to them. Highly experienced international long haul travelers may complain, but I suspect the casual traveler will be reasonably pleased. I actually appreciate the cloth seats here, as I think cloth generally keeps you a bit warmer and snuggly (as it were) on long flights. There's very little wrong with this plane.
I highly recommend choosing the "Main Cabin Extra" seats for the extra leg room. It will cost you some extra dollars if you're not getting it free as an American Platinum or Exec Platinum member, but our seats in row 21 gave us amazing leg room with very few drawbacks: 21A and 21B are some of the best economy seats I've flown in. I am 5ft 10in, and my feet barely even reach underneath the seat in front of me. There's a small equipment box underneath seat 20B, so you'll only have about 3/4 of the normal under seat storage in front of you, but your other things can be stashed in an overhead. I was a bit nervous sitting in an exit row as they're sometimes a bit cold, but the complimentary pillow and blanket helped me through nicely enough. Pack a compact pair of slippers in your carry on bag, and you'll be as comfortable as any typically sized human ever gets on in trans-Atlantic economy.
We're arranged in a two-cabin configuration, i.e. one First / Business class cabin in the front and a large economy class cabin in the back. There is no separate First / Business situation, nor is there any notion of Economy vs Premium Economy as found on newer planes. The higher end seats are arranged in a 1-2-1 (1 seat at the window, then an aisle, two seats in the middle, aisle, and then 1 at the opposite window) configuration, while the economy seats are arranged 2-3-2. I love this economy configuration in the 767, a big plus over the larger Boeing 777, because a couple can travel such that one gets the window, the other gets the aisle, and there are no interlopers to your little space.
On the subject of "your little space", the placement of the galley about a third of the way back in the plane creates an interesting enclave of two rows of economy seats in a small, more private little setting. I give mixed reviews to this because the second of the two rows has less recline, and the first is against the bulkhead (something I like, but others may not).
Food and Drink
Our flight ran from 7:10pm eastern time, and ran until about 8am Madrid time. This was good enough for dinner and then a light breakfast even for us peasants in economy. We chose between pasta or chicken with rice, and were impressed by both "for what they are". Our outstanding flight attendant, Kathy, was pouring a 70% Tempranillo and 30% Cabernet Sauvignon red wine blend. While not wine I'd often serve at home, it was some of the better airplane wine I've had. We recommend!
The 767s will eventually go away as the 787 Dreamliners offer a much better and efficient product. That said, economy on the New York to Madrid route is extremely doable so long as you go for the Main Cabin Extra seats and dress warmly enough to endure the exit row. It's a reasonable offering for the typical trans-Atlantic traveler.