Depends on what you mean by working. They're only measuring traffic, which is forced upon the user by their aggressive marketing campaign. It's not measuring clicks by actual interested consumers. Anybody could be top 10 if they wanted to spend the money to place their ads everywhere. I'm not impressed. I also think they're generating a tremendous amount of ill will.
www.zdnet.com/zdnn/stories/news/0,4586,5092788,00.html