Back on July 20, 2008, I asked: "Is YouTube about to pass Yahoo in expanded searches?" Well, I've just had a chance to digest the latest data from comScore for August 2008 and its appears that YouTube has passed Yahoo -- if you look at "expanded" search queries instead of "core" search queries.
First, what's the difference between an expanded and a core search query? According to comScore, a "core" search query is one that occurs on "the five major search engines including partner searches and cross-channel searches. Searches for mapping, local directory, and user-generated video sites that are not on the core domain of the five search engines are not included in the core search numbers."
If you expand the definition of a search query to include searches on YouTube, MapQuest, MySpace eBay, Craigslist.org, Facebook.com, or Amazon, then you get a different picture.
Google had 7.4 billion core search queries and 7.6 billion expanded search queries in August to lead no matter how you define a "search query." Yahoo! had 2.3 billion core search queries and 2.4 billion expanded search queries that month. But "YouTube/All other" Google sites had 2.6 billion expanded search queries that month. Microsoft sites had 977 million core search queries and MSN-Windows Live had 988 million expanded search queries.
So, depending on your definition, the top three search engines are either (1) Google, Yahoo! and Microsoft, or (2) Google, YouTube, and Yahoo! That is a distinction with a big difference.
By the way, comScore Video Metrix reports that YouTube accounts for more than 98 percent of all videos viewed at Google sites. (This means Google Video accounts for less than 2 percent of all vides viewed at Google sites.)
So, if you've optimized the pages on your website that contain videos, you've optimized them for Google Video and other video search engines. They won't help them get discovered, watched or shared on YouTube.
YouTube doesn't crawl the web trying to index videos posted on millions of websites. Instead, users are now uploading 13 hours of new video to YouTube every minute. So, getting your video found in about 2.6 billion expanded searches a month means uploading and optimizing video for YouTube, not Google Video.