The Xbox Live status shows there are a few issues accessing or retrieving data stored using cloud storage. The affected platform is the Xbox 360 Edition, where the problem started to occur around 3:57:40 AM CST.
Xbox members are being asked if they are having issues uploading Worlds in Minecraft: Xbox 360 Edition?
They are well aware of the problem and are addressing it right away, they also say thank you for being patient and as soon as they know more you will now.
Users must be signed in with your Microsoft account and provide a 10-digit US phone number if you wish to be notified when the service is fullu up and running.
Other areas of concern showing over on the Xbox Live status page shows the IGN app is limited, problems of launching the application is being sorted. There seems to be a Maxim issues as well.
Are you having any Xbox 360 problems?