After using this plugin on one of my multi user site. I must say that this plugin is sent from heavens.
I just have one question in my mind.
What is the manage_links capability.
What if I revoke this capability for my editors and authors who writes daily posts on my site.
Nothing bad will be happened in that case.
It is related to the widget which could show the list of links by your choice.
Read this article for more information about “Links Manager” and “Blogroll”: http://codex.wordpress.org/Links_Manager