I consolidated all my flying to AA after their AANYC offer early this year. That, and some non-flying miles offers landed me some nice upgrades (SFO-JFK and BRU-JFK, both done with miles) as well as awards tickets (JFK-EZE from the AANYC fares - which cost under $400 total!; NYC-YHZ and NYC-YYZ at 15K each shorthaul). Given that the two AANYC flights to California also netted me Gold status from a challenge I'd have to say that AA has been awfully good to me.

One of the most attractive things about AA was a very liberal upgrade policy, including the ability to upgrade discount economy fares with miles and no co-pay. I understand why that probably isn't great for their business model, but hey, I'm greedy.

Now that AA has instituted a co-pay for upgrading on international flights, which airlines remain with a more liberal upgrade policy?