After a few minutes, iMessages turn into text messages, and a visit to the "iMessage" Twitter account reveals a large number of tweets indicating that there are currently problems with the iMessage service worldwide, with many users experiencing outages. So far, Apple's iCloud website displays a "System Status" report, but it offers no details or updates on the issue. Hopefully, this problem will be resolved soon.

 http://www.apple.com/support/systemstatus/

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