Additional Results From 1st Rank Sites

Last Friday Google launched an update to their search algorithm which results in additional results being displayed for the top ranking website within the natural listings.
 
As written on the office Google blog, search terms that indicate a particular interest in a specific website will now return an additional set of results for the same website.
 
Users will now have the option to click on a 'Show more results' option, expanding the list of results from the website that they are interested in.
 
To keep the results set diverse, the remaining results are from other sites that follow the search algorithms.
 
Take a look at the official release article on Googles Blog.