Let's look at some of examples of spammy comments:

http://blam.sourceforge.net/images/decent_spam_example.gif .

What you see is irrelevant copy (nice site!, etc.) and a keyword-stuffed link anchor text, usually pointing to off-topic, high margin sites.

What Does the no-follow tag look like and what does it do?

Instead of linking to another site like this:

Another Site

a link using the 'no-follow' tag will look like this:

Another Site

When a search engine sees a 'no-follow' tag in an HTML link, it will not follow it, nor assign link popularity to the destination page. Search engines are encouraging blog software vendors and blog owners to use the 'no-follow' tag in blog comments and signature links. The theory is that if search engines stop following those links, spammers will stop posting.

Are spammers the only problem?

Unfortunately, no. Many websites have achieved high Pagerank and search engine rankings due mostly to links left by their webmasters in blog comments and signature link sections. While those comments and signature links may very well be relevant to the topic being discussed, their purpose, most of the time, is just to inflate the link popularity of the website belonging to the person leaving the comments. Being link popularity such an important component of good search engine rankings, this is clearly a loophole that needed to be closed.

While some webloggers are complaining that Google is throwing away the baby with the bathwater (punishing spammers and legitimate contributors alike), the truth is that comments and signature links in blogs are intended to point readers to other websites, resources or blog posts that may be of interest to them, and to foster a sense of community. Their objective is not (and never was) to increase the link popularity of weblog visitors' websites.

Will the nofollow tag be effective?

This measure may or may not stop comment spam. After all, humans can still see and follow spammy links, so spammers may still see some value (albeit significantly reduced) in continuing to post comments. What this measure will certainly do is to make link popularity more difficult to achieve. It will force webmasters to work harder and try other avenues to get links, for example, through directory listings, through syndication of useful articles with a link to their sites in the resource box, or simply the old fashioned way: by offering content so remarkable that other webmasters will feel spontaneously compelled to link to: just what the search engines intended when they made inbound links an important ingredient in their ranking calculations.

It is important to note that Google's 'no-follow' tag recommendation applies only to comments and signature links, not to the original posts. Links made from original blog posts will still be followed, indexed and weighted by the search engines.


Mario Sanchez publishes The Internet Digest ( http://www.theinternetdigest.net ), a growing collection of Internet marketing articles, tips and resources, and SEO Tutorial ( http://www.seotutorial.info ) , where you can learn the basics of search engine optimization in four easy steps.