I think a concept video, as long as it isn't too outrageous, is a decent way to inspire people. Some people watched minority report and said "I want to build that" -- concept videos could achieve the same. At the end of the article he mentions RIM's videos. I would say those are totally different as I think most of the basic components of that world are in the device or rumoured to be coming soon. That is cool. If someone can grab their latest device and make one of those workflows happen how good will they feel and what could come next?

Yes there are bad videos and they may have an unclear purpose but I think it is all about the context of the video.