What I have done is to set the RSS Feed forums up so that they require a password to view the threads within them. In this way, if you don't want to see them, you don't have to, and those threads will not show up in the
New Posts page.
The password is simply
enter.
This is the first time I have ever set up a password protected forum, so I don't know how persistent that entry is. In other words, if you enter once, I don't know if that entry permission is then stored with your login info in your cookie, and then you are ALWAYS able to enter that forum. Or perhaps it times out after you leave it, or you have to actually log OUT of the site to release that access.