you may have noticed the new Ignore button on these boards. this is a new feature just added, by request, which will allow you to simply tune out anyone posting shit that you don't want to read. all it does is prevent their thread posts from being visible - you will just see the user who made the post, with the post saying "you are blocking this users posts" or something like that. it's very easy to turn off and on.
i just wanted to note that this is NOT for PMs - that feature has already been in place, and if you want to block annoying people, just put their name in your Profile control panel.