Please welcome: Disqus
Disqus is a great tool and a great system for tracking comments, so now is supported on this blog!
You can use to let comments in this blog and in some others with the same Disqus account. It works really nice and is very useful, no only for this blog, also for many others!
Also you can use it with your G+, Twitter and Facebook account.
This is the first post that supports Disqus, so you can try it here if you want 😀