Head on over to American Airlines’ Email Promo Page, enter your AAdvantage number and let The Appraiser do his thing (cheesy video that you can skip). Once he’s finished, you’ll get a splash screen that tells you how many miles you qualify for and can click the “Yes” button on a series of pages to claim the miles. According to the T&C you have to remain subscribed to the AA emails for 3 months and the miles should post within 6 weeks after that. So, that’s about 4.5 months to wait, but free miles numbering in the thousands are hard to pass up.
This promo is directly proportional to how many of their email notifications that you already get, so not everyone will get the full 3,000 miles. In my personal experience, I received 1,000 miles and my wife received the full 3,000 miles.
Credit to FlyerTalk for filling me in on this promo.