The "Reply to Comments" feature recently lunched by Facebook. It is available for the Pages has more than 10K Fans. According to my experience with it.
- Easier to interact with individual people and keep relevant conversations connected.
- Ensures that people who visit the Page will see the best conversations.
It will be available automatically for all pages in July 2013. It can be enable from the admin panel.
I find it useful for both; users and Admins in many ways.
- With the growing number of fans for each page, you could find hundreds (even thousands) of comments on a single post. The comments ranking which set the most interacted comments at the top, and show them under the post instead of showing the latest comments really appealed me as a user. I believe it's an important addition to user experience.
- As an Admin, the ability to reply to each comment is a blessing with Facebook growing more and more as a customer support medium.