This article is not really about whether you should post listings on web directories but who should be posting your listings. I’ve already written an article here about the fact that listings on directories should not hurt you if the directory is a well run directory.
SuperPages.com and YellowPages.com are directories. There is nothing wrong with these directories. In fact, I run a directory which is a yellow page directory for criminal defense lawyers and has over 1,000 listings. The ads are really also listings with a website link.