Microsoft has previously admitted it "ran out of time" on a Windows Phone notification center, but it looks like the company is testing early future versions of Windows Phone with this feature in place. A Reddit user has posted a series of screenshots from a recently purchased Lumia 920 that appear to include an internal Windows Phone build. The software identifies itself as version 12084.WPMAIN(wpbldlab).20130509-1407, meaning it was compiled on May 9th. An early notification center can be seen in one of the screenshots, providing access to the typical Live Tile notifications.
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A Guy