Very useful for SEO, especially in increasing traffic and backlinks for your website, try to see a video http://www.youtube.com/watch?v=vpiCWXt91ko this I made it very fast and uploaded to Youtube. As all of us knew Google bought YT so every video that you upload to YT then it will be indexed quickly by GG robot..an important factor in SEO.
I agree with yestyle, you said right, posting videos on youtube are very helpful for SEO and increase traffic for your website. Otherwise, you also can earn money from your videos if they are quality and having a huge amounts of views on each video.
As we can say that it is a part of Content Marketing. Research across the world proved that the Most of Internet users spend more of their time to a site that has video of their own,we often pay more attention to the content which is visual as compare to written.
In the term of SEO , Video Marketing drives a huge amount of traffic to your site and gives you a well recognize reputation and customer base.
If it is embed it adds content value, if the videos page has links and descriptions that lead back to the website it is embed on, then that is when it adds value to your site because google can tell it is your video
Make a Quality informative video and upload it video submission & sharing sites like Youtube, dailymotion, Vimeo etc. with unique & High Quality meaningful description. Use Keyword(One at a time) in Your Title. They will help in your Website ranking as well as traffic driven.