Submitting to directories is one way of building backlinks to a site that are needed to rank well in the search engines. Is submitting to web directories worth it? Not a day goes by in which many people in SEO forums express an opinion on if it is worth it or not (also, not a day goes by in which many new web directories are launched!). The SEO kiddies love directory submission and see it as one of the key components of link building. The SEO professionals put less importance on it.
Personally, I actually think it is important and effective for a newish site in the early stages of that site and directory links do seem to make a difference. After a while and for a more well linked site, directory submission does not seem to be as effective. Due to the time involved and the relatively low costs, I use a directory submission service and get them to submit to 100 directories a month. Another option is to use a submission program like Submitease that can speed the process up.
What is wrong with directory submission is that the link is what I prefer to call a self promotional link. Self promotional links are links that are easily gained by self promotion. This includes directory submission, forum posting, article submission, blog commenting and social book marking. As they the types of backlinks that are easy to gain, assume that the search engines place less value on them that the links that are harder to gain and are given freely by other sites because your site is good. These links will still have some value, its just that it is not clear how much value they have. Also keep in mind, that your competitors will be out there submitting to get these links.
There are plenty of forum threads asking if the $299/yr for the Yahoo! Directory is worth it. Opinion is equally divided as to the value. I think it is you have a big enough budget for promotion. If your budget for promotion is smaller, then spend your money on other promotional means. The same goes for the $299 for BOTW. Aviva ($150), V7N ($50), Skaffe ($45), GoGuides ($40) and JoeAnt ($50) also depend on the budget, but generally are worth it as I see them (and maybe the search engines will also) as an important quality signal that this is a serious site and not a fly-by-nighter.
There are some issues about how the 1000’s of free web directories could be treated by the search engines.
One good one is BOTW which charges a lot, but they are very strict who gets in, which is probably why its worth getting listed. Some of the old directories like Skaffe, GoGuides and Web Experience who were around before the craze of a few years ago and have stood the test of time are probably worth submitting to. If you have health related sites, there are the old familiar ones such as ABC.md.