Here the Complete Features of Google+ Comments
- When you leave a comment on a blog, you'll see the option, checked by default, to also share that comment to Google+.
- Google+ posts that link to blog posts will show up as a comment underneath those blog posts
- If original comment is shared to Google+, replies to the comment on the blog will show up in Google+ and vice versa, but only to the people that the original comment was shared with
- If a comment is not shared with the blog author, the blog author will not be able to see the comment in either location
- As the author of a post, you’ll receive Google+ notifications when readers comment on or share your blog post. Source
Click here to know how to enable Google+ comments for your blog even using Custom Template?