Given recent disputes and requests for a feature like this, I've implemented an Ignore User feature. The content of posts and messages by users on your Ignore list will not be displayed.
To add or remove users to your ignore list, simply use the link next to each post (Ignore/Unignore) or, to manage your whole list, click Profile, then "Ignore user options" on the left menu, and add usernames (one per line) to your list.
Enjoy!
John Castellese
Web Developer
MonroeTalks.com