The brouhaha between 'good' writing and blogging is really an inability to recognize that blogging is to writing as small talk is to discourse. Without chit chat, important contextual info is missing from a 'real' conversation. Blogs and tweets fill this contextual gap. It's 'natural' from a linguistic point of view. Blogs & tweets (bleats?) help inform and cultivate a richer relationship between speaker & listener.
The following is from wikipedia on an emerging 'discourse community', developed by linguist Johnathan Swales: