Of course, the reason Chrome manages to auto-update itself is because it is installed into your home directory (i.e. under Documents and Settings or Users). This means every user on your computer has their own version. So while your version is up to date, less frequent users of the computer don't benefit from those updates. Because of the restart issue, they're always on the version that was installed last time around and perpetually unsafe. On my laptop, I've installed Google Chrome for Ubuntu using Google repos and Update Manager bugs me every time I log in. The technology still has a way to go. But, given Google's track record, I don't think it will take them long.