Blogger has just announced the much awaited feature "Threaded Comments For Blogger" and you might have already seen it on your Blog if you are using a default Blogger Template. If you are using your own custom Template, then you will have to tweak your template for the threaded comments to appear.
This is how the Threaded Comments will look like (Screen shot taken form the Official Blogger Buzz Blog)
How to get the Threaded Comments ?
1. Make sure that you have enabled Comment Feeds
2. Use the Embedded Comment Form.
3. Now If you are not seeing the Threaded Comments, then it means that you have a customized template.
There are different methods to fix this. But before doing any of those download a backup of your Template.
On the Old UI, you can get a backup at option in Design > Edit HTML > Download Full Template
If you are using the New UI, then you can find the same at Template > Backup/Restore (Right Side) > Download full Template
Tweaks to get the Threaded Comments:
1. The simplest method is to reset each of your Widgets to default. Doing this will revert back any customization which you or the template designer has made to the Widgets.
You can reset the widgets by going to the Edit HTML page, and clicking on the link which says “Revert widget templates to default” . If you tried this and lost your Customizations, you can always get them back by re-uploading your Template using the Backup/Restore option
2. If you don’t want to reset the widget templates, then you will have to manually Edit your template.
Find each occurrence of this snippet
<b:include data='post' name='comments'/>
and replace it with
<b:if cond='data:post.showThreadedComments'> <b:include data='post' name='threaded_comments'/> <b:else/> <b:include data='post' name='comments'/> </b:if>
and you should probably see the threaded view on your blog. If that too doesn’t help leave a comment here and we will try to debug it together :-)
Once you enable the threaded comments, your blog will by default show the 200 oldest comments, and you will see a load more link which will help the reader in viewing the rest of the comments