I'm not surprised that lots of people use an outdated version of Jetpack. It consistently fails to auto-update for me, to the point where I used the notification as a sign to visit the jetpack site and upload the contents of the zip file via FTP. This is through no fault of the developers (nor mine) but more a problem of my host. I imagine many hosts (and their customers) would not be thankful for auto-updates that had the potential to cripple sites.