Improves the built in "Link to existing content" dialog. Provides filters, has optional shortcode support and improves searching.
Seamless integration with the wordpress UI. Control of the post types and taxonomies you want to be able to link to.
Shortcut functionality for internal links, so they don't break so easily in the future (server move, rewrite changes, …)
The options page for the plugin, introduced with version 1.5
An example of how a shortcode link to another post looks like
a taxonomy archive link in the frontend, automatically parsed by the plugin
a post-link in the frontend