A directory such as Yahoo depends on humans for its listings. You submit a short description or editors write one for sites they review. A search looks for matches only in the descriptions submitted. Updating your web pages has no effect on your Directory listing. Ways to improve a listing rank in a search engine do not apply to a directory. With Directories, a good site with plenty of useful content could be more likely to get reviewed or be reviewed sooner than a poor one.
What are directories?