I got turned on to the disqus comment system by Shey Smith on his most excellent blog, http://sheysmith.com and got really motivated to install it when I heard Leo Laporte and Amber Macarthur rolling in the aisles over this on their net@nite podcast broadcast live today.  It helped push me more that Dave Winer, grandaddy of rss and blogs, is using this as well.

Disqus brings video comments, along with a community of commenters, better comment formatting, and much more.  And the wordpress plugin install was as easy as could be.