I would like to request a hook that would allow a plugin to check some stuff and possibly prevent a comment being added.
Why? My plugin adds age, gender and location information to comments. I want to ensure this info is entered *before* the comment is added to the DB.
I can work around this by hooking to the form's onsubmit, or by deleting the recently entered comment after hooking to the 'comment_post' event, but these are hacks, not good solutions.