The Zune HD may not have seen quite the explosion of apps that many had hoped for, but it's just gotten a pretty big one: Windows Live Messenger. That will naturally give you much of the same functionality of its desktop counterpart (also receiving an update today), including the ability to keep watch on updates from various social networking sites, and even use Facebook Chat. It'll also display the music you have playing right in the app and, just like the desktop version, it's free. Look for it in the Zune Marketplace right now.

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