You should search Nielsen NetRatings. You will notice that they own the first 4 spots in Google.
Guess which one is their current site:
All three sites have the same content. Why would Nielsen NetRatings create three duplicate sites? Why would they maintain 3 different domains but not different content?
Your gut reaction is that they have made a major SEO blunder by not redirecting the older versions of the NetRatings content. Yahoo! sees roughly 550k links spread across the 3 sites: Nielsen-Netratings.com (400k links), Netratings.com (27k links), Nielsennetratings.com (127k links). This search opens up a couple of interesting questions:
How does a page with a single external link showing beat the index and a similarly named domain with 4 times the domain links?
Why does Nielsen canonize www, but not domain names
the first quest probably has many answers. The second question leads me to believe that Nielsen is trying to saturate their brand by creating multiple strong domains for their name. Giving up 20k or 100k links to mirrors is a small price to lock down multiple first page results.
This leaves a more important question: Why does Google allow their results to show 3 identical sites? You would expect the search algorithm to strip out content that has been indexed across multiple sites, especially when they are all running from the same server, you can tell because NEWS returns an error on all of them today.
If you start tracking a page across the multiple versions of Nielsen NetRatings you will probably learn a thing or two about how duplicate content is handled and rather base attempts at brand protection that are normally suppressed in Google search results.
Thanks to Christopher Darrell of Dhammiko E-Commerce Consulting for pointing out the NetRatings results.
