Automattic Kismet (Akismet for short) is a collaborative effort to make comment and trackback spam a non-issue and restore innocence to blogging, so you never have to worry about spam again.
Installing Akismet is absolutely no problem at all, since it comes bundled with your WordPress installation. However, using it requires you to have a WordPress.com account.
Akismet is available in two flavors, the personal version which is free for use and the commercial version which is meant for those earning more than $500 from their blogs or for commercial usage. Commercial keys have better service and no limits.
The major plus point of Akismet is that it is updated in real time. The service learns which comments are spam and which are not.
When your blog receives a comment, pingback or trackback, it is submitted to Akismet for verification. If Akismet identifies this as spam the same is notified to the plugin and it is flagged as spam. Good comments come through and get posted.
The spam comments are stored in a database for your review and are deleted automatically after 15 days.
There are currently few perceivable problems with Akismet.
Another problem with using Akismet is that you rely on a single service to protect you. There have been a few instances in the past when the Akismet server when down and blogs were filled with hundreds of spam comments in a matter of moments. Many of these landed in the queue, some got posted.
The new version of the plugin made it easy to handle these situations with a recheck queue and the ability to search through the comments in the spam queue for false positives.
Akismet is definitely providing a fantastic service to not just the WordPress users, but users of other systems for which plugins to use Akismet have been written. It is indeed a boon for most normal users, but it should actually we auto activated and made to run without an API Key or a default API for users who don’t even know that they have to turn it on to prevent spam.
For more experienced users, just relying on Akismet isn’t a recommended solution. You should have a self hosted protection for your blog, which could optionally use akismet as an extra test.
Are you running Akismet exclusively? Have you faced any problems with this? Have they resolved satisfactorily?
Ever been flagged as spam? What did you do then?