Use case: Sometimes when I'm tracking a particular work item for a project I want to be able to add notes to a particular task (rather than updating the status or adding a comment).
Wrike offers this ability and its really helpful. Each task can be double-clicked and it opens a description where the project manager can add task specific notes, thoughts, or attachments. These are internal notes for the project manager, not conversations. It's a very a clean-UI and helpful.
Currently, I'm using a workaround by using the comment section/or adding a comment (not great).