This was being discussed on another thread here, so I thought I'd see what others thought. Is it for any of these?
- Letting off steam about language misuse seen elsewhere on MN
- Having a general moan about abuses in the wider world (at work, in the media etc)
- A more educational purpose of allowing people to get clarification around something in their own writing or in the writing of others
- To inform about points of pedantry on any subject (not just English language)
Of course, feel free to add other options, just thought a few suggestions would help.