Today, August 23, Apple pushed out the first update to OS X Mountain Lion. The update can be downloaded through the Mac App Store or through a direct download.
To run the update, open the Mac App Store, click “Updates” in the upper right of the app, and wait for the update to appear. Follow the on-screen prompts from there. The 20-30 MB file addresses fixes for iMessage, Migration Assistant, and audio on Thunderbolt displays.
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