Interfacing between credit cards and Bitcoin can get complicated and risky so while I've read and heard of companies that have offered that I have never used them myself.
But here is the problem to be mindful in your own dealings - when you buy with a credit card you can contact the credit card company for even quite some time after a transaction and claim the purchase was wrongful in some way. You can claim you never received the item, that it was defective, was not the agreed upon item or a host of other reasons and the company will reverse the payment to the seller/merchant and take the "money" that was paid them back. This is called a "chargeback" and is a policy followed by all credit card companies (as far as I know).
Bitcoin is not a company, however, and there is no way to reverse the Bitcoin transaction after it was made. It is also difficult for the seller to prove to a third party (sic. credit card company) that they sent the transaction.
Considering the large amount of credit card fraud, the buyer may in fact be using a stolen credit card number. In that case too, the payment would be chargedback. So a seller is taking a risk when they sell Bitcoin for credit card payments.
The bottom line is that credit cards are 50 year old technology and very, very insecure (especially on the Internet).