Atlassian has introduced Confluence 4.0 with a number of new enhancements. One of the most impressive changes is the addition of their new editor:
A new streamlined toolbar puts new users at ease with familiar editing operations exactly where they're expected. A single editor makes for a more reliable experience for your users and saved work that looks exactly like what was crafted in the editor. What you see is really what you get.
Check out this screenshot of it in action:
This new editor also converts your wiki markup automatically to rich text. Other improvements include additional keyboard shortcuts, macros and buttons on the toolbar to make editing content that much easier.
Another unique new feature is the @mentions capabilities. Similar in a way to the functionality that Facebook and Twitter have incorporated, @mentions allows you to engage others in conversation while editing a post or replying to a comment.
Here's a great video showcasing some of the features: