In VeryBusy, you can tell at a glance whether the comments and markups you've left have been addressed, and you can indicate to others that you have addressed certain comments.
Accompanying each comment/markup in VeryBusy is a circle that appears upon hover; clicking it will change it to a green check mark, which allows you to indicate to your fellow collaborators that a comment has been addressed.
Keep in mind that although some comments may be marked complete, the image will not change until a new round is uploaded.
When a new image round is uploaded, all comments marked as complete will be hidden; they can be revealed by changing the menu at the top of the comments panel to "All Comments" (it's set to "Unresolved Comments" by default).