An article directory is one of the easiest ways to get a backlink for your site
. I think everyone knows that there are a few big players and a lot of little players. I'm a person that likes to have a diverse link portfolio. That means I like to have resources to get links from many different IPs as possible. And you really can't do that if you're just using a few of the big sites because after a while the links will stop helping you. I thought I could help you determine which ones are actually good.
I want to start out by saying that a lot of the so called "small" directories are actually quite good. They typically have faster approved times, more considerate staff and still provide solid links.
A big issue that I see all the time with some small article directories is that my articles don't ever index in the search engines. This is a cause for concern. I've been to directories that have a listed volume of a quarter of a million active articles on their site, yet they only have a few hundred indexed pages. That type of directory will never index your pages and will be a total waste of time for you. Make sure there is anywhere between a few thousand to a million indexed pages (depending on the size of the directory).
Many people like to look at the PageRank (PR) of a directory to determine how good it is. I suppose PR could give you an indication of what you might get back from the directory, but I don't really look at things like that. I like to go through the directory at random and pick an article that I think focuses on a modest keyword. I'll search the keyword and see where the article ranks. The better it ranks, the better I view the directory.