Automattic the team behind open source blogging platform WordPress has acquired IntenseDebate – a blog commenting service, that provides a replacement for the default comments systems to WordPress, Tumblr, Blogger, Moveable Type and other blogging platforms. By installing the plugin, you get threaded comments, reputations, and other advanced features. And readers can track their own comments and those left by others across any blogs or web sites that use IntenseDebate.

With this acquisition IntenseDebate will temporarily going into an invite only system — new users will require an invite code. Matt and Toni also posted about the acquisition.