Add an additional card to any American Express by 12/31/11 and get 10,000 membership rewards points. bonus id 5721 and you get 10,000 points for every card you add!!
you have to call and add the person thru the rewards department so they can give you the points.
Small update: Minimum age is 16, SS# and DOB is required.
Additional user is required to make 1 purchase before the 10k points will be posted.
Couldn't find this on the site yet. From what I'm hearing you might have to call up a couple of times to get it seeing as its a targeted offer.