Well the rumor is that Lulzsec hacked xbox live. But there has been no official release from lulzsec. No one has stepped forward to claim an xbox live hack either. I don't think it's a legitimate claim as of yet.
There are tools to check your email address against all the recent hacks all over the web. My email is still safe as of right now.
edit: Even if it was hacked, more likely than not you don't have to worry about your credit card numbers. Companies (smart companies) don't store credit card information in plain text. In fact large companies like Microsoft leave payment data responsibilities to a 3rd party. I'm not saying I know Microsoft does this as a matter of fact, but smart companies leave PCI compliance to 3rd parties.