Xbox Live is currently suffering some issues:

Users may experience difficulties with the following services:

• Creating new Xbox LIVE accounts, managing those accounts, or recovering an account on a different console
• Buying downloadable items from the Xbox 360 console, Xbox.com, or Games for Windows – LIVE
• Paying for downloadable items with a credit card
• Signing into Games for Windows – LIVE on a PC
• Redeeming downloadable items with Microsoft Points, buying additional Microsoft Points, or viewing your points balance
• Using prepaid cards or codes for downloadable items or Xbox LIVE subscriptions
• Purchase transactions using the Games for Windows LIVE client.

We are aware of the problem and are working to resolve the issue. We apologize for any inconvenience this may cause and thank you for your patience
Users may experience difficulties with the following services:

• Users may be unable to render the maps within the Call of Duty: Modern Warfare 2 Stimulus Package Map Pack.

We are aware of the problem and are working to resolve the issue. We apologize for any inconvenience this may cause and thank you for your patience



Follow the issues here: Xbox LIVE Status: NXE | Xbox Support

All seems to be good now

I got banned for a day for no reason, maybe this stuff was the cause.

You can now keep track of the status of Xbox Live by just looking in the sidebar here The information is pulled directly from the Xbox.com's status page, so it will always be up to date.