I prefer cards rewarded in dollars rather than points. It's harder to devalue dollars.
In my wallet:
Costco AMEX 3% gas, resturants 2% travel, 1% everything else. The annual fee is also the Costco annual fee, which I'd spend anyway.
Discover for their 5% promos, plus they have some discount gift cards. I usually spend these at Crutchfield. The gift cards used to be a better deal than they are now.
Capital One MC - No FOREX fee. Otherwise a boring 1%.
In my Lock box against a day of need:
Citi AADvantage MC - Got for the promo. Will drop when the fee comes 'round.
Citi AT&T VISA - Lousy rewards. It is my oldest CC, so I keep it barely alive to maintain my credit score.
Chase Subaru MC - 3% in Subaru bucks. Mrs Scubadiver loves her new Outback.
AMEX Blue - I got this to try out the smart-card chip. Don't use it now. No fee so I don't cancel it.