A note on Airline cards versus "Air Miles" cards that aren't tied to one specific airline. You've probably heard the Capital One ads about how their card has no blackout dates, or similar advertisements for air travel cards from Citibank and other credit card companies. These aren't the same thing as an airline's own MasterCard, Visa, or American Express cards. In my opinion, they aren't as good a deal as the actual airline cards. Why? Because the only way you earn miles is from charges. And that means you don't get a free trip until you've spent some $25,000 on that card. That could take years. While with a real airline card, every dollar you spend is a mile going into the airline's own frequent flyer program, combined with miles you earn from flying that airline and its partners, miles from car rentals, hotels, dining, telephone, and other promotions. It's the combination of flight, spending, and non-flight travel that gets you the free trips quickly. The bank air miles cards don't have that combination feature.

What airline card to get? That depends on which program you've joined. American, Continental, Delta, Northwest, United, and U.S. Airways, the six "major" carriers in the U.S., each have their own airline credit cards. You only need one or two of them, one for each program that is your "focus" program. As I've mentioned, you should be running only one or two programs as your "focus" frequent flyer programs at any given time. With the airline alliances, that's enough to cover most of the airlines you might fly.

For example, don't get both a US Airways Visa and a United Visa. Why not? Because you shouldn't be trying to earn miles in both the US Airways Dividend Miles and United Mileage Plus programs. Both airlines are part of the Star Alliance, so you only need to be in one of the programs to earn miles in that program from flights on either airline. Pick either United or US Airways, get the card that matches the program you picked, and when you fly the "other" airline, use the frequent flyer number for their partner. Same for Continental, Delta, and Northwest: They are all in the SkyTeam alliance, so just work one of them. In my case, I use the Delta Skymiles American Express Credit Card, use the Delta Skymiles program, and whenever I fly Continental or Northwest I give them my Delta frequent flyer number. That way I maximize my miles instead of spreading them around. Even if I want a free trip on a Northwest flight, I can use my Delta miles, which I earned in part from my Delta credit card, to get the trip.