[OzStarGazer]

It has been "reported" as unsafe - but by whom?
Can anyone report a site as unsafe?
If this is the case, it could even be a banned spammer who has reported the site as unsafe (as retaliation).

Edit: If you go to Safety in IE, you will see that there is indeed a link to report a site as unsafe. I am not sure if the warning appears immediately after a site is reported or only after their technicians have looked into it. I do have the safety settings on in IE by the way, but get absolutely no warning.