commenting on forum topics and blog posts
These links are shown because we've setup the commenting system so that you can reply to specific comments (threaded commenting). This means that each comment has links beside it. When you are logged in, you simply see one that allows you to reply to that comment. If you are not logged in, then you will see the message prompting you to register and login if you want to post a reply.
The alternative is to display comments as a flat list, where new comments are simply added at the end. This would not need the additional links and prompts, but the style of commenting would be less 'conversational' than it is with the threaded view.