Google is without question the Internet’s most popular search engine, but within the last year, YouTube eclipsed Yahoo! as the second largest. The average American user visits YouTube 23 times per month, and each session lasts on average 26 minutes. As well, the video search giant reaches more than five and a half billion views per month. Any way you slice it, there are a lot of people frequenting YouTube. And for the purposes of SEO, there is a lot to work with.