In my opinion. the only time you should place a video on a website or blog is where the aim is to show how to do something. A video is an ideal tool for demonstrating how to make an omelette, repair a puncture, or darn or sock. But not for most other things.
The worst examples are videos where the author is simply speaking to the camera, giving information that would be much better presented as well-written text. Often the presenter speaks the text without any preparation, giving the impression that he was too lazy to plan it in advance or to write it down (a certain well-known member of Google's staff is one of the worst offenders here).
Personally, I would prefer to receive this kind of information as written text. This has the advantage that you can choose either to skim it or to study it in depth; you can read it at a time and place convenient for yourself, without disturbing those around you; you can print it out, copy and paste into a document, transfer it to your ebook reader, search it, or translate it; and you can do all that without consuming excessive bandwidth.
That's my personal opinion, I know that there are people around who prefer watching a video to reading a piece of text. That's their choice. But personally I hate having to have to watch a video in order to obtain information that I can consume more easily as straightforward text.. I also believe that there are too many videos on the web which exist simply because the author was too lazy to write their thoughts down.
If you really must use video to present your thoughts, at least provide a text transcript of it as well.