website previews in Safari marks forums read

I have a problem, not with this forum as I haven't been here a while, but some I read regularly.

They are in my "top sites," so when Safari visits them to update their appearance for the new tab page it marks that I've been there, so when I actually go there, I miss things under "since last visit."

Any idea how to fix this? Thanks.

 

I think I didn't explain my problem clearly in Safari.

You know if you open a new window or a new tab it brings up the page with your "top ten," visited sites ? It also updates those window previews at intervals I'm not sure about.

However, thats bad, when it opens the page of a forum, and then it marks threads read you haven't actually read since the browser only went there for Safari background stuff.

No way to turn this off?