A long time standard among countless blog users, Akismet now has a more formidable competitor in Defensio now that Websense has snapped up the company.

Both companies offer a service that lets blog, forum, and general Web application users to easily integrate anti-spam technology to guard against comment spam. The technologies typically work by sending certain aspects of comment data to Defensio or Akismet for analysis where a result is quickly returned that determines the likelihood that a given comment is spam.

Karabunga, Inc. is the company behind Defensio, which has now been acquired by Websense. Terms of the deal were not disclosed.

Akismet is backed by Automattic, makers of the widely used Wordpress content publishing platform.

Both anti-spam systems allow free non-commercial and varying prices for commercial users. Akismet has long enjoyed the advantage of being part of the Wordpress distribution package which is now used by millions of sites. The latest version of Wordpress, 2.7 released in December 2008, has already been downloaded well over 1,520,000 times as of January 2009 - all of which makes for a readily available user base.

Now that Websense has acquired Defensio it too can expand exponentially by leveraging Websense's long time customer base.

Opinions differ though on which solution is actually better although some feel that Akismet is easier to use. Accuracy is what matters most though when it come to blocking spam. Towards that end, Akismet openly publishes statistics about it's success rates on the site home page. So far Defensio only publishes an average success rate on its home page.