So are the people that have received this updated release early in one regional area or spread around the county? When I bought my Droid, I was walking out the door when it coughed up the latest release!
All updates are done randomly. Where did you see someone received it already?
If you are running and have set as default the Helixlauncher 1. Would that need to be switched back to the original 2.1 launcher before the 2.2 update?
You shouldn't have to change anything. The update is all automatic, there is nothing you need to do to "prepare" for it. If you feel better about switching launchers then do it, but it's an app. It shouldn't have anything to do with the update.