A WebmasterWorld thread reports one Google AdWords advertiser has been upgraded to the new AdWords Editor, version 5.
I reviewed the release notes and there is no mention of version five. I downloaded the latest version and that version is still version four. I checked Google for mentions of a version five and found this post from yesterday. The post says, he met with Alex from the Google New York office and Anva from the Mountain View at a Singapore training event. In that event, they told him "AdWords Editor 5 is to be released soon this week" and version 6 is in development.
I would expect the release of version 5 to the public within the next 7 days.
The one change in version five mentioned in the thread is how the tabs are laid out. The member in the thread said, the "new tabs in the main screen allow the editing of placements and local business ads."
Forum discussion at WebmasterWorld.