When it comes to credit card rewards, a cash-back program still rings the consumer’s bell. Nearly half of U.S. consumers prefer cash-back over air miles, flexible points, purchase rebates, or purchase discounts. However, air miles come in at a strong second place. According to a recent home page poll conducted by CardWeb.com, nearly 34% of consumers listed air miles as their favorite credit card reward. Flexible points, which can be used for anything from merchandise to travel, came in at a distant third. Slightly more than 8% of the 1,058 survey participants voted a points program as their favorite reward. Discounts at the point of sale appealed to only 6% of consumers, while purchase rebates was the favorite reward for only 3% of Americans. Little wonder why so many issuers have launched cash-back cards and air mileage cards in the past 18 months. American Express says its cash-back program has proved so popular it has extended it to the “Blue Card” and some of its “Business Cards.” This week, Discover launched two new cards, one offering air miles and the other offering cash-back for gasoline purchases.