I went to the site to see the newly posted Russian version of the PowerShell for AD video with Jeffrey Snover and myself – and had to install the Silverlight plug-in to do that.
I think this was the first time (apart from the web pages on Silverlight itself and demo prototypes such as Tafiti) when Microsoft started doing that. Of course this should help drive wider adoption but at the same time I guess you need to be sure that the content is valuable enough for the visitor to install the plug-in – which was the case with me wanting to watch myself on the video.
UPDATE: It looks like they now also added (or it was there from the get go and I just did not notice it) the option to download the wmv version of the video. It is just that it is somewhat below and in smaller font so Silverlight is a much more noticeable option (and the only one for video streaming.)