Pretty much like any other forum.
Numerous "creative writing" forums exist on the web, in many languages. Considering that getting one's writing published isn't the easiest of tasks, it makes sense that people who write are happy to post their writing to a forum where they can be assured of a readership. And considering that there seem to be lots of still unpublished authors around who have discovered these forums, that readership really isn't so small. Many of these writers have had the common experience of having something they've written refused for publication, and they want to respond positively to others, as they hope those others will toward them. It should come as no surprise that some of these forums are even quite large, and many of the participants don't relate to the reactions to their writing they receive from other members as a consolation prize for not getting published, but instead as a source of pride.
Which forum a particular unpublished author finds and joins is on the whole of question of chance. Members of any particular forum are probably convinced that the level of writing in their forum is highly professional, while others are filled with crass amateurs. I doubt that outsiders would be able to tell much of a difference.
Go to: If you knew him like we knew him.