How many of the video posters on Youtube should have articles included about them in Wikipedia?

Answer 1

If all they have done is upload videos to YouTube, they shouldn't have a Wikipedia article about them. Wikipedia has notability criteria which must be met before a person's biography is included. You can read it at http://en.wikipedia.org/wiki/Wikipedia:Notability_%28people%29

Biographies will only be kept if the person has been "the primary subject of multiple non-trivial published works whose source is independent of the person". Self-publishing a video on YouTube doesn't count!