I'm in the process of looking at blogging tools to do something very similar. I'm kinda worried about having a history though in a few years that shows I only post during interview times :D.
I don't post that often. When I get stuck on a problem because of poor documentation or poor explanations I just make a tut off that. Mostly focused on other things right now though. Making a video is a lot of work. Come up with a project, a script, rewriting your explanation, fill in your gaps in info, voice recording, video editing. It adds up.