The Federal Reserve thinks that banks have been charging merchants way too much for the convenience of processing debit and credit card transactions. Over the next year, lower interchange fees may not exactly result in lower prices at your favorite store. However, you'll probably notice some subtle changes to your favorite card reward programs, as banks look for easy ways to recoup some of that lost revenue. Watch your mailbox for alerts about the three most likely reward program changes:

#1. Tie benefits to other bank products.
With debit and credit card issuers collecting fewer fees from each transaction, some banks may try to preserve their best rewards for customers who help drive other kinds of revenues. Don't be surprised if you start seeing some major banks offer their best cash-back credit cards to customers who maintain high-value savings or checking accounts. Some of our editorial team's favorite credit cards of 2010 already require deposits at banks or brokerages, so you can expect that trend to continue in 2011.

#2. Squeeze advertising into your online statements.
Credit card issuers have slipped ads into mailed statements for years-- you know, those special offers for record clubs, collectibles, magazines, and various consumer items attached to your payment envelopes. As more consumers opt in to electronic credit card statements, the extra ad revenue from statement stuffing has dwindled. That's why some credit card companies have started sneaking ads into their online statements. Watch for special offers appearing adjacent to related purchases: buy a burger at McDonald's, for instance, and see a coupon for a competing fast food chain.

#3. Use rewards to steer you away from PIN-based purchases.
Payment processors responded to new banking regulations by opening up their networks to multiple fee schedules. If you use a debit card that offers both swipe-only and PIN-based transactions, your bank may start offering you extra rewards when you swipe. Higher merchant fees cover the cost of your bonus miles and cash-back rebates. Merchants have started experimenting with rewards of their own to encourage you to enter your PIN, so you may have to consider both offers at the checkout line.

Although banks must issue clear notifications in plain English whenever they change the terms and conditions of your core debit and credit card accounts, reward programs don't always fall under the same rules. Check your mailbox for nondescript envelopes that contain details about your rebate or reward program.