Blog owners crave comments.
Someone who takes the time to leave an intelligent response to a blog post is telling the author that they appreciate what they have seen- even if the person leaving the comment does not agree with the author.
But what is in it for the person leaving the comment? The benefits to leaving comments can be the difference between the site featured by the person leaving the comment (we will call that person the commenter) showing up on the front page of search engines, and not showing up at all.
How is that possible? Most blogs allow comments, and when the commenter fills out the required information they must put in a name, email address, and the comment.
In most cases they also can include the URL of a web site.
If the administrator of the blog approves the comment and it becomes a visible part of the blog, that link to that website is retained in memory and becomes a link to the commenter's site, something that the search engines will consider when ranking that site.
The more links into a site, the higher potential ranking the site can achieve.
Of course there is much more to SEO than incoming links, but just by itself, it's a powerful tool for SEO when done properly.
Recognizing the potential power of those link spawned the rise of spam comments done both manually and automated.
Blog owners can usually add spam filters to eliminate much of the problem with the automated commenting systems, but spam placed manually is much more difficult.
My rule of thumb is that the comment must refer to something in the post to be considered worthy of being approved.
A comment like, "That was a great article.
Keep up the good work," could be copied and pasted on every blog post on the internet.
If you are a blog owner, as much as you may want to allow a comment like that, resist the temptation.
Wait for quality.
If you are the one leaving the comment and you want that incoming link to remain rather than being marked as spam by the blog owner, read the post and add value to what has been written.
Give another perspective.
Offer a deeper look into the topic.
Tell the author what you feel about their post and why.
Chances are the blog owner will value the comment, approve it, and you have an incoming link to your site that is likely to last for the life of that blog.
To add to your chances of being approved, get a Gravatar tied to the email address you will use so your picture shows up on blogs that allow an Avatar.
Your picture next to your post comment rather than some blank icon shows you are a person and the blog owner is sure to take that into consideration when deciding to accept or dump your comment.
There is so much to the topic of blog comments but these are basic guidelines that will help both the blog owners and their commenters to more effectively coexist.