Strange Domain Stacking in Google SERPs? (UPDATED with Google announcement)

One of our co-founders here at WebShare discovered something very strange last night, and we are still observing it today. Spurred by a random discussion about TV shows, he performed a google search for this old house and saw the following:

The first 7 results are all from same domain??? Typically we see that a domain can have a maximum of 2 URLs appearing in a given query in the Google SERPs (not including the indented results).

We were able to replicate the scenario using another search for webshare conversion marketing:

8 URLs from the same domain on page 1. Very strange.

We were able to replicate this from different locations in AZ and CA, so it doesn’t seem like geolocation is a factor.  Are you seeing the same results?  Do think this is just Google experimenting?  Or maybe just a glitch?

What do you all think?

********UPDATE***********

After confirming these results with a few other people at SES San Francisco, I did a little more research and found the following blog post by Malcolm Combs where he’s discovering the same results:

Google treating brand names in search terms as site: searches?

In the comment thread is an interesting point from Bill Slawski where he believes this activity may be associated with what is described in a Google patent:

This looks like the process described in Google’s patent “Query rewriting with entity detection” (US Patent 7,536,382). which was granted in May of last year.

For example, the process might identify Apple as a specific entity that is associated with a specific web site, and rewrite the original query to provide results from the Apple site. From the patent:

Some entity names are unambiguous and uniquely identify particular entities. A large number of names, however, are somewhat ambiguous or generic, making it more difficult to identify the entities to which they are intended to correspond when included in users’ search queries.

Systems and methods consistent with the principles of the invention provide mechanisms for determining the entities to which entity names correspond and selectively rewriting users’ search queries based on the entity names. Accordingly, a user’s search query may be restricted to a search of document(s) associated with the entity that the user intended in the search.

There doesn’t appear to be any official indication from Google whether they are just testing this algorithmic change or if it’s here for good.  This kind of change may benefit big-brand entities, but I don’t believe this is a benefit to the searcher since the search results may not be the most relevant.

********UPDATE #2***********

Official announcement from Google regarding the algorithm change:

http://googlewebmastercentral.blogspot.com/2010/08/showing-more-results-from-domain.html