Good question.

"I care for you" can mean any variation of the following:

1. I really like sleeping with you but that's about it.
2. You're a cool person and all but I don't really see this going any further than it's already gone.
3. I care about your life.
4. If you got hit by a car, I'd wish you were better and didn't get hit by a car.
5. If you were mauled by a lion, I'd probably send you a card.
6. If you're having a bad day, I might not want to hear about it, but I'd really wish you could have a good tomorrow.
7. I kind of like you. I'm just not sure what that means myself. I'd definitely not stop dating if I were you.
8. If I don't have anything better to do, I'd definitely hang out with you, and maybe even pay.
9. I like spending time with you when I feel like it.
10. (If said by a chick) I love you but I'm afraid to say it out loud until you tell me first.

What it doesn't mean (assuming a man is saying these things):

1. I love you.
2. I want to marry you.
3. I want us to have children together and live in the suburbs of Des Moines.
4. I can't wait to see you everyday.
5. You're the first thing I think about in the morning and the last thing I think about at night.
6. I'd like to talk to you on the phone a lot.
7. I'd be willing to meet your mother and father.
8. I'd like you to meet my friends.
9. Valentine's Day is our special day.
10. I love you.