Originally Posted by Thunderroad

FWIW, here's a long post I wrote a little while ago comparing many facets of the AA and UA programs, especially (but not only) from the point of view of a UA 1K/AA EXP member.

http://www.flyertalk.com/forum/unite...p-changes.html

The bottom line is that I felt, at the time, that UA had fallen behind AA. I wrote it shortly after UA had dropped its confirmed regional (that is, mainly domestic) upgrade instruments (known as CR1s) and made other negative changes. Now that UA has restored the CR1s and provided some modest additional benefits by virtue of its cooperation with CO, I think the UA and AA programs are again roughly on par, with lots of pros and cons on either side of the ledger.

One key feature that remains to AA's advantage, though, is that its VIPS tend to be much more useful than UA's equivalent (system-wide upgrades, or SWUs) or UA's CR1s in that AA makes them available for upgrading at time of ticketing much more often than UA does. This could yet tilt me in favor of prioritizing AA, but I'll now wait and see how things play out in my experience with both airlines over the next several months.