If you are serious about ranking a site organically, especially an ecommerce site, it is always beneficial to list in Yahoo Dir. If you can get your listing in a category that has good pr, down the road your site might rank there (it doesnt go alphabetically like business.com) and can be very valuable. Also helps with authority so you dont get penalized for buying links in the link sales forums Ive never seen a listing not get 'accepted' and have listed there maybe 15 times.