IntenseDebate
is a Free comment flatform which let your readersconverse with their own social networks like google accounts, facebook, twitter
and even an open source comment
IntenseDebate features
- Comment Threading.
- Reply-By-Email.
- Email Notifications.
- Commenter Profiles.
- Moderation/Blacklisting.
- Reputation Points & Comment Voting.
- Plugins API.
- OpenID.
- Widgets.
- Twitter Connect.
- Facebook Connect.
- RSS Readers & Tracking.
2.Add your blog to IntenseDebate, Click on “My sites”

How would you like to install.
select "Template" option.
Which blog posts should have IntenseDebate comments enabled?
Only on new posts
Your old comments will be displayed using your blog's native comment system
On all blog posts
IntenseDebate comments will be available on all posts, but your existing comments will be hidden.
Select "On all blog posts" option.
3.Scroll down to the bottom of the instructions.
4. Log in to your blogger dashboard--> Design--> Edit html.
back up your template

Now upload the template you have backup to IntenseDebate
After Uploading

5.Go to your blogger dashboard--> Design--> Edit html.
6.Select entire code in the Edit Template text Box and delete it.

7. Save your Template and you’re Done!!!
You can see my Comment Box For the Live Sample