Update: I have added a link to the Platinum charge card review, and updated the information about the Platinum charge card earnings based on this press release:
Beginning October 6, consumers with a Platinum Card from American Express will receive 5X Membership Rewards points on airfare booked directly with airlines or through American Express Travel.
Update: I have added links to the Premier Rewards Gold charge card review as well as my explanation of Membership Rewards.
American Express offers charge cards which are similar to credit cards in the sense a charge card is used to pay with credit rather than directly from your personal bank account. The differences between charge and credit cards are the lack of a hard and definitive limit to how much can be spent on the card (think an invisible credit limit), and the statement balance has to be paid in full by the payment due date without the option of paying a fraction or small amount of the full statement balance.
The Green, Gold, Premier Rewards Gold (PRG), and Platinum cards are the four charge cards offered by American Express. Charge cards earn Amex no money by means of interest like credit cards so each charge card comes with an annual fee: $95 for the Green and $450 for the Platinum cards with the Gold at $160 and the Premier Rewards Gold card at $195. However, each card earns at least 1 Membership Rewards (MR) point per $1 spent on any transaction (no cash advance for charge cards) with the perk of earning 2 MR per $1 spent at amextravel.com. MR points can be used for a variety of things such as paying for something or as statement credit, redeeming for gift cards, or transferring points to airline and hotel partners or Plenti.
Both Green and Platinum cards earn 1 point on anything and everything without any bonus categories, besides 2 MR at the Amex Travel site. The Platinum card offers numerous perks well worth the $450 annual fee, where as the Green card does not offer any perks (not even access to The Hotel Collection) despite having that $95 annual fee. The Platinum card now earns 5x MR points on tickets directly from airlines or on flights purchased at amextravel.com.
Additionally, the Gold and PRG cards each offer 2 MR per $1 spent at restaurants as a bonus category, and offer access to the aforementioned The Hotel Collection hotels found at amextravel.com. The PRG has category bonuses which are not offered by the regular Gold card: 3 MR/$ on airfare purchased directly from airlines, 2 MR/$ at gas stations and supermarkets.
I will go into further detail on the perks offered by the Premier Rewards Gold and Platinum charge cards in future posts outlining the benefits of each card. Each card has an annual fee but the fee can be greatly decreased making the card (and perks offered by each card) have an effective lower cost.