I am trying to decide whether to enroll in the American Express Skymiles Card. Is is worth it? I usually use my Discover Card to get the CashBack award each year, but I am wondering if I should start using a credit card to earn miles for flying to Disney! We have flown TWA, Delta & Southwest, but it is always based on who offers the best fare. Any suggestions on what, if any, card is better? I haven't a clue on how many miles it takes to earn a free ticket. I always see these ads "earn 10,000 free miles!!", but I assume that sounds better than it really is. We fly from St. Louis, MO or Nashville, TN (we live about in the middle of either one of these airports. Does anyone have an idea of miles needed to earn? Thanks for any imput!