Vertical search has been around for almost as long as the major search engines have been in existence. Some of the first vertical search engines were for image search, newsgroup search, and news search, but many other vertical search properties have emerged since then, both from the major search engines and from third parties.
This chapter will focus on strategies for optimizing your website for the vertical search offerings from Google, Yahoo!, and Bing. We will also spend some time on YouTube, which in January 2009 became the second-largest search engine on the Web. First, we will look at the data for how vertical search volumes compare to regular web search volumes. The data in Table 9-1 comes from Experian Hitwise and shows the top 20 Google domains as of May 2006, one year before the advent of Universal Search.
Table 9-1. Most popular Google properties, May 2006
Google Image Search
Google Video Search
Google Book Search
Google Desktop Search
Back in May 2006, when images were not shown directly in the web search results, image search comprised almost 10% of Google’s search volume. With the integration of image results ...