I've honestly never seen the point of vlogs. YouTube is an audiovisual medium, and I'm only interested in watching a video if it has content that absolutely needs to be aural and/or visual. For example, Let's Plays and music videos. Both of them make for great YouTube videos.

But if you're just a talking head, I'm not interested. I'd rather read a blog post. I read faster than people talk, and I honestly don't have the patience to sit there and listen when I can read the same words in a written essay in half the time.