Originally Posted by sdsearch

If you have good credit, there's more: Visit the "Other credit cards" forum and look at the Citi "60 day" thread. You can not only get a 25000 bonus, you can get multiple 25000 bonuses right now (again, nothing to say it won't change next month), just by applying for a new card every couple months (and spending $750 on each of those cards in the first 4 months).

There's no other airline, and no other card group, that I'm familiar with that you can do this with. So if you can take advantage of this "loophole", you may be able to get AA miles for upgrades way faster than miles for upgrades at any other airline.

And yes, Northwest and United both require that you buy comparitively high fares (just a slight step below "fully refundable") to qualify for upgrades. If you buy tickets far in advance*, then it tends to be cheaper to upgrade at AA, even with the co-pay. (It's only for people who buy tickets comparatively "last minute", when all that's left is those higher fares anyway, for whom UA or NW upgrading doesn't cost any more than AA upgrading.)

*And remember, your chances of actually getting the upgrade go up if you book earlier, for multiple reasons.