rankings
The Internet is a niche market ripe for Ezines on rankings. A rankings Ezine could include tips, articles or relevant information on rankings. These articles should be well written and to the point. Subscribers do not have a lot of time to read big articles unless you are sharing new groundbreaking information.
Try to determine what Ezines already exist on rankings. They may only cover once aspect of rankings. Authors who launch a rankings Ezine are only successful if they remain true to their subscribers. They have taken the time to write because they are interested in rankings and seek to service that field.
