What is this comment system plugin? Is there a template script of the comment system somewhere and also what plugin is that for all the different types of login for comment.
link here: goo.gl/QM7Ek
Surely this is the default wordpress commenting system, as the site is running on wordpress.com.
It's possible it's Automattic's IntenseDebate as it would make sense for them to use that on their wordpress.com network:
An alternative would be DISQUS:
Note both of these are hosted solutions, but they integrate very nicely into Wordpress (as well as other publishing systems).