Like the Web Preview screen that I talked about yesterday, the Tag Editing screen is one that has existed for a while but sees a significant update in version 2.4.
Rather than just allowing you to select from your own tags, Yummy now goes back to Delicious.com and asks for recommended and popular tags for the link in question.
As you an see in the screen shot, it also shows your network, allowing you to share your bookmarks with other Delicious users.
