There are almost 15 videos in the SEO category alone, ranging from interviews with Matt Cutts
from SMX Seattle (he discusses duplicate content, among other topics), to tutorials on the basics like title tags, best practices, and how to run a site health check.
Meanwhile, there are 10 clips on content and link building, including SEO Book's "How to: Create Link Bait Every Day," and primers on social bookmarking. There are also a number of videos that tackle site usability issues, the plethora of contextual advertising options, as well as tips for e-commerce Web sites.