A few days ago I added OpenID support to Wordpress using a plugin. That plugin allowed me to log into WordPress using OpenID, and also allowed commenters to use OpenID to log in to comment on posts.

Today I remembered IntenseDebate which is an integrated commenting service that completely replaces the stock WordPress commenting system. Bonus feature: OpenID support. Double bonus feature: Facebook Connect.

I easily added IntenseDebate through a plugin that they provide for WordPress. In fact, late last year, the company behind WordPress actually acquired IntenseDebate meaning the integration is very well done.

The other choice for this kind of commenting service is Disqus. I’ve used Disqus in the past and liked it plenty enough. They have OpenID support, Facebook Connect as well as Twitter for logins, but I went with IntenseDebate primarily because of the acquisition by WordPress/Automattic.