Defensio boasts a few features lacking in Akismet, most notably the ability to sort your blog’s blocked comments by “spamminess” so you don’t have to wade through them chronologically to find false positives. Defensio will rank comments that it labels as spam according to how likely it thinks the comments are indeed spam, listing the least likely comments on top. The blocker will even color code your blocked comments to help you find the ones you want to approve.
Defensio also adapts to the content of your blog so that it can target spam more effectively. It’s success at blocking the right comments for each individual blog can be tracked, so you’ll know just how well Defensio is performing for you.
Among Defensio’s other innovations is an open API that makes the blocker available for use with non-blogging applications. Defensio also provides RSS feeds for your comments (sorted by spamminess, of course) so you can track them outside of your publishing platform.
Today, the company releases plugins for both WordPress and Pixelpost, and they may release one for the CMS Umbraco as well. Plugins for Rails and .NET developers will also be available. Defensio plans to develop plugins across a wide range of platforms over the coming months.