This days every webmaster owns a directory. This is a good way to exchange links, make money, increase AdSence clicks. Hard to belive that people pay $150 or $199 yearly to BOTW or Business.com.
Many pr5-7 directories apeear every Google update and all of them promoce that they are #1. How to understand if directory good or it another scam.
1. Look pagerank. Directory should have good pagerank even 3 clicks away from homepage.
2. Always check at least 3-5 websites submitted to directory before you submit yours. Ignore directory if too many 404, cheap sites like 1 page offers, adSence sites, adult contest, redirects. Search Engine spiders check all links on the page. Bad neighbors can hurt your SERPS and TrustRank.
3. Never submit to directories if they ment "Increase PR if you submit on our pr6 page" or "Buy pr5 link". Prefer directories who tells you more about traffic, business list. Google does not like when you buy links to increase pagerank. Moreover, Google might already ignore all links from directory and you never know.
4. Check directory metatags. All pages should have different metatags related with category.
5. Always look how old directory.