With the easy creation of videoclips today and the ever growing amount of video clips available out there, it is quite important to make videos interesting otherwise they will not be viewed much at all. But before you press the play button you probably look for the lenght of the videoclip, to make sure it has a duration you can afford to invest of time wise. For me this value various depending on topic, mood and other external factors. To learn more and get a bit scientific about the subject here is a good post by the people at WebVideoCrew that actually have some interesting facts that applies in general.