I think business cards should speak a bit toward individuality. I use a slightly different paper for mine --- a parchment patterned cream. I list my name, address, phone and e-mail, plus the genres I write (since I do both freelance and novels.) Once you get agented and/or published, you might consider adding your agent contact information at the bottom and one author gave me a super idea: have your recent backlist (title, ISBN, release date) printed on the back! I do leave enough room to do what Jim suggests, writing down info.
Several people at conventions have made favorable comments about my cards, and being remembered is always the goal with cards.
When I return from a convention, I take the time to send an e-mail to each person I met, thanking them for taking the time to talk to me. It keeps that friendly contact going so that even a year later, they'll probably remember my name if I e-mail them.
Have fun at the convention!