I have found several V2 examples of how to pan the map while a marker is being dragged. For example: http://www.putyourlightson.net/projects/coordinates
Google has fixed this: http://code.google.com/p/gmaps-api-issues/issues/detail?id=2404
You can see the fix in action at http://www.publicgloucester.com/test2.html. Ignore the comment that says "it doesn't do what I want"; that comment is obsolete.