Ya directories do work.. In fact submitting your site to directories is the best way to have your site indexed by search engines, build quality back links to your site, target specific keywords and phrases.. Ultimately all this leads to your site getting a higher rank and more traffic..
Directories should be at least with PR 3. They do not sent you traffic but you will get more links. I prefer to do bookmarking because they do not only give me links but sometimes traffic also.
yes surely the directories gonna work , benefit of getting your link included in web directories is that your link is indexed by the search engines quickly. Search engine crawlers crawl the Internet to obtain information on the recently updated or created links, and they start the crawling with the web directories and first crawl all those links present in the directory.Every search index the already-validated links, which saves your time and gives benefit and increase your page rank.