Move Error in Migrating to iCloud

I was trying to migrate from MobileMe to iCloud to get the 25GB account that will last only until June 30, 2012. But for some reasons, I always failed to move to iCloud. I have tried to sign-in to iCloud using my Apple ID but it still failed. Does anyone here encountered the same error or migrated successfully?
Can you help me?

Move Error
We encountered a problem while moving your account. You can try to move your account to iCloud again in an hour.
You can continue to use MobileMe.
