It sounds to me as if it's very similar to what has happened on Yuku just recently whereby ads are containing malware.
Here is the information given by Google when one tries to enter the site and on clicking the malware warning.
I will keep you updated as and when I can find anything out.
Safe Browsing
Diagnostic page for top-site-list.com
What is the current listing status for top-site-list.com?
Site is listed as suspicious - visiting this website may harm your computer.
Part of this site was listed for suspicious activity 10 time(s) over the past 90 days.
What happened when Google visited this site?
Of the 739 pages that we tested on the site over the past 90 days, 57 page(s) resulted in malicious software being downloaded and installed without user consent. The last time that Google visited this site was on 2009-03-19, and the last time that suspicious content was found on this site was on 2009-03-19.Malicious software includes 72 trojan(s), 6 scripting exploit(s). Successful infection resulted in an average of 6 new process(es) on the target machine.
Malicious software is hosted on 12 domain(s), including g00gleadserver.com/, hikayeler99.com/, adtoall.com/.
4 domain(s) appear to be functioning as intermediaries for distributing malware to visitors of this site, including you-tobe1.blogspot.com/, you-tobe.blogspot.com/, trlist.gen.tr/.
This site was hosted on 2 network(s) including AS21844 (THEPLANET), AS15169 (GOOGLE).
Has this site acted as an intermediary resulting in further distribution of malware?
Over the past 90 days, top-site-list.com did not appear to function as an intermediary for the infection of any sites.
Has this site hosted malware?
No, this site has not hosted malicious software over the past 90 days.
How did this happen?
In some cases, third parties can add malicious code to legitimate sites, which would cause us to show the warning message.
Next steps:
- Return to the previous page.
- If you are the owner of this website, you can request a review of your site using Google Webmaster Tools. More information about the review process is available in Google's Webmaster Help Centre.
