For my purposes (and inclusive of redemptions on partners), I still have it that AA ranks higher (and significantly so) than UA/US; and, in turn, UA/US ranks higher than DL/NW/CO when it comes to award availability space. However, for my purposes, the award availability gap between UA/US and DL/NW/CO has significantly narrowed, narrowed to the point where sometimes (i.e., with that "sometimes" being increasingly frequent) DL/NW/CO passes up UA/US if willing to tolerate a few more connections.

Looking at this from award rules flexibility, I'd place AA first, followed by DL (although DL is slipping a bit but not enough to make it worse than UA), then UA followed by NW/CO.

Overall, I rank AA's program better overall than the other major US carriers that fly intercontinental long-hauls. And While UA wasn't so far behind AA for my redemption purposes a few years ago, UA is now increasingly further behind AA for my redemption purposes. I'd say it's still:

1. AA
2. UA
3. US
4. DL
5. NW
6. CO

.... but, over time, the gap between AA and UA has widened while the gap between UA/US and DL/NW/CO has narrowed to the point where I'd say it's:

1. AA

with 2. UA as a distant second
with 3. US riding on UA's coat-tails
with 4-6 DL/NW/CO behind but gaining quickly on UA/US