I re-head recently about Google Knol, which is IMO some crossing-over between a wiki and a blog.
Are there some people that use it here to write haskell-related articles instead of a regular blog?

As far as anybody outside Google knows, Knol has pretty much been abandoned. See http://googlesystem.blogspot.com/2011/01/abandoned-knol.html . I don't think it's worth contributing knowledge to it.