For as long as I can remember there has been a debate on the value of directory submissions, and while I tend to agree that the value of a link from most directories is very low, there are a few that you should have in your link profile.
Unfortunately for the paying customer, these are pretty much at the premium end of the directory scale, and therefore hit the wallet hardest. In this list I would include BOTW, Business, GoGuides and Yahoo. Why do I think they’re important? Well mostly for the trust I believe that Google has in these sites, and therefore a link from them to your site flows a little trust as well.
I’ve recently submitted a site to the Yahoo directory, and they created a new category for it that is currently un-cached..