Several comments to my last post, “Comment Luv – Linky Love – NoNoFollow” inspired me to dig deeper into the subject of blog spam (also referred to as comment spam). I wanted to know why blogs get spammed, and what we can do to prevent it.

Today’s Lesson

Wikipedia, states spammers are on a mission to elevate their websites in the search engine rankings. By linking to blogs they obtain more links pointing to their sites. Apparently this method is working. Spammers are gaining sales/income via clicks from visitors. Spammers hit the “jackpot” with the creation of blogs.

According to Wikipedia,

In 2003, spammers began to take advantage of the open nature of comments in the blogging software like Movable Type by repeatedly placing comments to various blog posts that provided nothing more than a link to the spammer’s commercial web site

Several of the solutions listed by Wikipedia to block comment spam, include

1) Keyword blocking – blocking words such as viagra (spammers know of this practice and will intentionally misspell words)
2) Using the “rel=”nofollow” code. Wikipedia states the argument against this is:

Some weblog authors object to the use of rel=”nofollow”, arguing, for example, that

* Link spammers will continue to spam everyone to reach the sites that do not use rel=”nofollow”
* Link spammers will continue to place links for clicking (by surfers), even if those links are ignored by search engines.
* Google is advocating the use of rel=”nofollow” in order to reduce the effect of heavy inter-blog linking on page ranking.
* Google is advocating the use of rel=”nofollow” only to minimize its own filtering efforts, and to deflect that this actually had better been called rel=”nopagerank”.
* Nofollow may reduce the value of legitimate comments

3) Validation, or the use of a potential commenter to provide an “answer’, such as “is fire hot or cold”, “2+2″ or to retype a series of numbers and letters (CAPTCHA)
4) Disallowing links in post comments
5) Using a spam blocker such as Akismet
6) Turning comments off.

Short of turning comments off, it appears blog spam (comment spam) is here to stay.

Today’s Assignment

How do you deal with blog spam?

Do you use a spam blocker or hand moderate each comment?

Do you have any other ideas of how spam can be eliminated?