American Express Membership Rewards - Double AMEX Skymiles

Just got a flyer in the mail:
Receive double skymiles for all purchases over $500 from Nov 1st-Nov 30. Maximum bonus miles earned is 10000.
Seems to be targeted as it is 'good for Selected Cardmembers only' http://www.flyertalk.com/forum/frown.gif

Information on a variation of this offer can be found in the Delta forum at http://www.flyertalk.com/forum/Forum21/HTML/012179.html