Netflix is offering 2,500 American Airline miles for new subscribers. If you already have a subscription and just want the 2,500 miles, you can use different information (address, email, and credit card). I just subscribed through this offer yesterday for the $8/month online membership. You can always cancel your membership at the end of the month. Click here to join with this special promotion.
The terms and conditions state: Please allow 8-10 weeks for mileage postings. A Netflix membership is a month-to-month subscription that you can cancel at any time. Click here to view full list of T&C.
UPDATE: My bonus American Airline points have already posted to my account. Kudos to Netflix and American for posting so quickly!