how would the card stop someone from from hacking/setting the machine to give every couple votes to whoever the hacker/programmer wanted to win (or paid him for the votes)?
say a voting machine in a predominately democratic district ends up showing 100% votes for Bush. the magnetic card thing keeps track of who voted, and that ends up checking out OK, but how do you keep track of how many votes were actually cast for each candidate? cards only keep track of who is voting, and if they have a right to. you can't record the vote cast by each card or you lose the privacy of your vote. you can't check the count when something seems wrong because all you have for proof is the very program that gave you the first answer.
kind of like needing a second opinion on a medic issue and getting it from the same DR who gave you the first one.
