I'm considering to apply for an American Express Blue Cash card.

"Blue Cash" is a cash rebate credit card from American Express. It boasts the following top features:

- Up to 5% cash back
- No annual fee
- 0% Introductory APR
- Pay over time
- Built-in Smart Chip for Internet Security

Be careful: the "up to 5% cash back" feature is not much better than the typical 1% flat cash back from most cash rebate offers in Visa and MasterCard labels. The fine print explains why:

First, Amex maintains two cash back schedules: "Everyday Purchase" and "Other Purchases." Everyday Purchase is defined as purchases "at stand-alone U.S. supermarkets, gas stations, drugstores, and home improvement stores."

For "Everyday Purchases," the first $2,000 in a year earns a cash back of 0.50%. The next $4,000 earns 1.00% cash back and anything above (until $50,000) earns 3.00%. For "Other Purchases," the cash back rate is half of that for "Everyday Purchases" (that is, 0.25% for the first $2,000, 0.50% for the next $4,000 and 1.50% for anything above $6,000 to $50,000.

Second, Amex offers a bonus for carrying a balance. The bonus is 2.00% for "Everyday Purchases" and 0.50% for "Other Purchases."

So, in layman's words, one can only enjoy 5% cash back if he spends more than $6,000 a year on Everyday Purchases, and maintains a balance (thus are subject to interest rates from 8.99% to 13.99%). At least for me, I don't expect to spend that much in supermarkets, gas stations, drugstores, Home Depot and Lowes every year.

I should say the main reason I want to try out this card is because I am a CostCo member. As CostCo does not accept Visa and MasterCard credit cards, I cannot get any cash rebate for my CostCo activities. I do expect I can get some cash back by using Amex Blue Cash at CostCo. For $1,000 annual CostCo spendings, I expect a $25 rebate. (Another option is Amex Cost Cash Rebate Credit Card -- available from CostCo.com. It offers 0.25% cash back for the first $2,000, 0.50% for the next $3,000 and 1.50% above $5,000. Another 0.50% bonus if account carries a balance.)

Currently my preferred credit cards are ShareBuilder Visa and an MBNA reward card, both offering 1% flat cash back (the latter actually gives you $200 for $20,000 spending -- which I'm at $18,000 now). I prefer the ShareBuilder Visa more because it sends you $25 whenever you accumulate another $2,500 spending. Maybe once I try out Blue Cash I will switch my preference -- barring any Amex acceptability issues, I can break even with Blue Cash (compared to 1% flat cash back) if I spend more than $13,000 per year, which seems to be achievable.