WordPress.com is working on making it easier to interact and maintain your blog. It's improving the notifications area that it introduced a few months ago adding comment notifications but also ways of moderating comments right from the notifications box.
"Today we’re adding comment notifications, complete with comment moderation and reply functionality. When your post receives a comment, you’ll get a Notification," WordPress.com announced
"You will see Approve, Spam, and Trash links in your comment notification if you have permission to moderate comments," it explained.
Threaded comments are also supported, so you'll know if you've gotten a reply. What's more, you'll be able to reply a comment from a small pop-out box from the notifications area. Basically, the most important ways of interacting with a comment can be done without visiting the blog post or the dashboard.