Ok, since Badcat has posted about Solomon Kane and Savage Worlds, I checked out their free quickstart rules.
It's interesting. The use of different die sizes has been around for a while. Sovereign Stone and Serenity are a couple off the top of my head that use this as well. I can live with that approach.
Savage Worlds also uses a deck of cards in play, and has some mechanics that are named off of card terms.
There are several systems that utilize cards in the game mechanics. Torg, Lace & Steel, Masterbook, etc.
I like West End's Masterbook approach where it is an optional rule.
I am not a fan of cards or any other play aid that is not a die or dice. I guess I am just colored by my first experiences of roleplaying, and see these additions as extraneous.
What do others think of using cards as a game mechanic in a RPG system?