Update: I'm not a big fan of any game that requires me to spend money to be good at it, but I can definitely see the appeal of Magic and CCG's (collectible card games) after playing Card Hunter. It's a "Freemium" game but you're not disadvantaged much if you only want to play the free content.
It's pretty fun, I spent several hours playing yesterday. If you have some time to burn and you like strategic grid-games, and/or CCG's, and/or Dungeons & Dragons, then you should give it a shot.