I'm in debt but its interesting to see my score fluctuate (improve!) over time. Getting the cards isn't the bad thing, lest you have outrageous fees. Having and using the card establishes said credit history in which additional lenders will trust you with additional money. Some places, ala cell phone companies require a credit check or you will have to pay more per month instead of enter a contract, especially if you know you will be with them for atleast a year. Don't forget car rental places, too.
Moving on, they offer much better protection than debit cards or cash. By law, you are only liable for up to $50 dollars worth of unauthorized charges, if that. Plus, you are using the banks money, not your own (at the time of the transaction), so you will have the backing of the issuing bank to go after the merchant who fufilled the order.
I'm trying to get to the point where I can minimize or eliminate my debit card usage, relying on the protection provided by my CC and simply paying off in full every month, but for now I only use them for large purchases.