malware?

It's not because of MacRumors, but because of a link to a blog which may contain malware. I wouldn't worry, since a link or image can't really hurt you. I actually got the same screen when I tried to enter my work's private website.

 

A user made a forum post with an embedded image from that site. When you viewed that page of the forum thread the alert warned you about an apparently suspicious domain, even though the user was making an innocent post as far as we could tell. I don't know whether or not the warning was valid, but the image link was in fact broken so the moderators removed the post. There's nothing further to be concerned about.