In a tremendous article at Search Engine Land, Danny Sullivan discusses the details of “blended search”. This is a term Sullivan uses to describe the new wave of changes to the search results. Once solely the domain of web pages, SERPs are increasingly showing results from other mediums: maps, images, videos, blogs, news sites, and so on.
Google’s SERP is the most well known for returning blended results, thanks to its Universal Search algorithm. Other search engines have claimed to be following suit, but there hasn’t been much coverage of their efforts in the US, which is typically the testing ground for algorithm changes.
Here in Australia, Google users are starting to see blended results for searches involving a specific location, e.g. “department store Sydney”. Instead of only web pages, searches like this trigger Google Maps results – which often occupy the top 3 positions in the SERP!
The article talks about how the real term to use to describe this is “Search 3.0″ seeing that “Search 1.0″ would have been based on location, frequency, & on-the-page ranking criteria, and “Search 2.0″ began looking at links & other off-the-page criteria. He then goes on to discuss the imminent “Search 4.0″ that takes into consideration social aspects and personalisation.
A great diagrammatic representation of Universal Search is also given:
I’ve only skimmed over the outline here so I highly recommend checking out Search 3.0: The Blended & Vertical Search Revolution.