One-way-Link from web directories are a sought of link farms that need to be avoided while submitting your websites. This is a lesson that I learnt by paying a price for ranks on Google.
There was a trade-off between the ranks of my site in Google and the submissions that were accepted in the recent past.
I had learnt that the directories that have a less popularity should not be considered while submitting your websites. The popularity is in terms of their visability on search engines, their Tristrank and their page ranks. TrustRank is a way to cut down on spam and filter out content that is not relevant to the searcher in order to bring them results they really want. What this could mean to you in the near future is that linking to a non-trusted site would deem your site untrustworthy as well. It is so important to be careful to whom you link.
Consequences of linking to black-hat websites can be severe. Google terms Trustrank as, “Web spam pages use various techniques to achieve higher-than-deserved rankings in a search engine's results". While human experts can identify spam, it is too expensive to manually evaluate a large number of pages.
Instead, we propose techniques to semi-automatically separate reputable, good pages from spam. We first select a small set of seed pages to be evaluated by an expert. Once we manually identify the reputable seed pages, we use the link structure of the web to discover other pages that are likely to be good.
We hardly see any link farm websites on the Internet these days. This is because they have taken the form of a Link Directory. Listing on such link directories IMO may get our sites drop in ranks on Search Engines like Google.
