We've got a lot of messages about this yesterday (5/10/2012).
If you had visited the Google Safe Browsing diagnostic page you would have seen that:
Of the 172 pages we tested on the site over the past 90 days, 0 page(s) resulted in malicious software being downloaded and installed without user consent. The last time Google visited this site was on 2012-05-10, and suspicious content was never found on this site within the past 90 days.
Our admins haven't found any signs of badware on the site. It may have been caused by malware distributed through a third-party ad network. We are working with our ad network partners investigating this possibility. It could also be a false positive from the Safe Browsing.
We requested a review from Google yesterday. As a result we've got the following:
Status of the latest badware review for this site: A review for this site has finished. The site was found clean. The badware warnings from web search are being removed.