I just found out today that the US Bank "Cash Rewards" Credit Card policies have quietly changed (assuming you don't read the small print on the "cardmember agreement" that apparently silently changed in 2007).
Your "rewards" (cash) now "expire" if not redeemed (ie. cash transfered) within 3 years. They just started to take this money in November. They do NOT indicate that they are taking this money away on your statement, instead the starting Balance + Rewards Earned does NOT equal Ending Balance. I guess it was too much to put a line in to say "Rewards Forfeited" to show the negative number and make the balances add properly. This might have had the unintended effect of making people NOTICE they were taking your money.
They don't seem to have a problem with this new policy, but DID have a BIG problem with me calling it BULLSHIT.
US Bank is now on the list of UNTRUSTED BANKS (that apparently can't do simple math on their statements).