World of Warcraft: Cataclysm Beta Client Updated to Include Background Streaming

A new client has been released for the World of Warcraft: Cataclysm beta, which "includes new features that allow you to stream game data while you play. This will reduce the time you spend downloading and patching World of Warcraft once installed."

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Shacknews has asked Blizzard for clarification on what this means for the end-user, though it sounds like it will let Blizzard stream changes and minor patches in the background, reducing the frequency of patches.

It does not sound like it will replace the patching process and it remains to be seen if it will change the weekly downtime during maintenance. In any case, if you're in the beta, uninstall your client and download the new version through the Battle.net account management page. You cannot patch up to this version.