Something interesting you may want to check out is the Symantec website that shows stats on the websites with the most threats detected. It is astounding the number of threats some sites have. Some have had threats for over 5 months. Now I have to be critical here that Symantec should be a good netizen and follow up with the ISP’s that host these to remove these sites, at the very least it should be attempting it and showing that in their reports.
Check out the report website here