With $500/month that means $6,000 per year. At a 1-1 earn rate (which is just about the best you can hope for at the moment) you will get 6,000 pts a year. At this rate of earning you will be probably be only interested in using points on economy fares, and given the $$ of surcharges that now apply to award tickets, the best you can hope for is a redemption rate of 2c per point. So you will get $120 worth of points a year.
Therefore, if you are going to have a credit card anyway - I'd say make sure that the amount you'd pay for a card with rewards attached to it is no more than $120 dearer than one without - that shouldn't be a problem. As for which one to get.... I'm afraid I'll have to defer to others.
Credit cards which earn frequent flyer points is a popular way to earn frequent flyer points. You can receive thousands of points on everyday spend. And, many of these cards offer generous signup bonuses! Compare to find the credit card that best suits your needs.
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