- Is it ranking in the SERPs? - If a site ranks well
in the search engines it stands a good chance to be trusted by them.
Plus even if those links do not count to help boost your ranking they
still can drive direct traffic. I frequently see directories like
Business.com and JoeAnt ranking in the search results.
- Do they sell direct links? - Direct links are
more likely to be taken as editorial votes of quality. Some redirected
links may still count, but many of them will not.
- How frequently is their site crawled? - You
need to check and see if the category pages are being cached in Google,
and how frequently they are cached. If their pages are not getting
cached or have not been cached for 6 months then the odds are pretty low
of that link carrying much weight.
- What is the quality ratio? - Does it list
anyone who pays? Or do they hold sites to some quality standards? Do
they categorize sites properly? Or do they sell links to anyone in any
category, even if it is the wrong one? Does each page have unique
content? Are most pages empty - adding nothing but clutter to search
indexes? If they do not help engines categorize the web (ie: no
editorial value) then eventually the engines are not going to trust
their votes.
- What is the ad ratio? - Are all the listings
paid? Or will they list some useful sites without payment? Does the site
look like it aims to serve end users? Or does it look like it exists
just to get AdSense ads or affiliate ads indexed?
- Do they sell outbound sitewide links? -
Prettymuch the equivalent of selling out - when a directory puts
sitewide outbound links on their site (especially if those links are to
junky sites) the odds are pretty good that the links are not going to
count much.
- Is it decrepit? - Directories which have 50%
of their links broken or pointing at URLs that have been purchased by
spammers or domainers are not going to pack as much punch as sites which
have few broken links. I recently bought a 25 page directory that has
not been updated in a couple years, and it had about 400 broken links in
it. Not good!
- Does it have unique content? - Is it a DMOZ clone? Are its listings manually compiled and unique from what is offered at other directories?
- Is it relevant to my site? - Many small niche
directories can drive decent value due to offering decent co-citation
data and having exceptionally relevant traffic streams.
Bob Mutch recently rated 40 top directories
based on their age, how many edu and gov links they have and whether or
not they are listed in DMOZ and Yahoo!. I would contest that WhatUSeek
isn't a real directory, ISEDB is a directory of search engines and
directories, and that Vlib.org should be counted as a directory, but
other than those minor points this is a pretty cool study.
I think the inbound link profile is a good starting point for rating
(when you add it to the other criteria I mentioned above), but what I
think is even more interesting is how quickly they fall off in the
quantity of quality links.