Get ready for what you know about credit cards to change: The bulk of the Credit CARD (Credit Card Accountability, Responsibility and Disclosure) Act of 2009 went into effect on February 22, 2010. These disclosure laws are aimed to protect consumers, so it’s in your best interest to brush up what will affect your credit card usage the most.

You have a rate freeze on any outstanding balances. However, you might have seen your APR go up in the last couple of months, which is the bank’s way to trying to make up for the billions of dollars in losses sure to follow. Pew Charitable Trusts found that interest rates surged by an average of 20% on credit cards from last December to July.

You get fair warnings about card changes. Consumers will be given a 45-day notice to any changes in credit card terms, which can include rate hikes on newer cards or fees. This gives you enough time to decide if you want to close, pay off or transfer the account. If you decide to negotiate for a new rate, the new rate is effective immediately.

You need to watch out for new fees. Citigroup said it will charge an annual fee to some cardholders who don’t rack up enough expenses in a year. Also, transferring balances from one card to another will be more costly, as the Pew study found these fees jumped 34%.

You see how long it will take you to pay off the balance. Statements must now clearly disclose how long it would take you to pay off your current balance based on your interest rate. This can be shocking information if you choose to only pay the minimum: On a $1,000 balance it could take you 15 years if you have a typical 15-20% interest rate.

For more detailed information about all the laws (plus more CARD Act laws going into effect in August 2010), go to this MSN Money article.