Do you want to continue editing your important documents on a flight without wifi? Now you can! We have launched one of the most requested features. Users now have the ability to edit documents and leave comments offline. You must be running the latest version of Chrome or ChromeOS and install the Google Drive Chrome app to edit offline.

Editions included: 
Google Apps, Google Apps for Business, Government and Education

Languages included:
All languages supported

For more information:
http://googledocs.blogspot.com/2012/06/announcing-your-two-most-requested.html
http://support.google.com/docs/bin/answer.py?hl=en&hlrm=en&answer=1628469

Update:
This is only available to domains on the Rapid Release track.

whatsnew.googleapps.com
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