Add Comments and Votes
MindMeister's Opinions feature enables you to leave comments on individual topics and vote them up or down. This is a great way to discuss ideas with your map collaborators without cluttering up the mind map.
How to Comment and Vote on a Topic
1. Select a topic in your mind map.
2. In the bottom area of the sidebar on the right, switch to the Opinions widget.
3. Click on the Thumbs up or the Thumbs down button to vote on the topic.
4. Write your comment into the empty comment field and click Say it to submit it. You can use the Icon button to add icons to your comment.
How to Read and Reply to Comments
Comments and votes are indicated with icons on the right end of a topic. The vote icon not only shows that votes have been cast, but also indicates the relation of up-votes and down-votes.
You can view the voting details as well as the comments by hovering over or clicking on the icons.

How to Emphasize Popular Ideas
At the top of the Opinions sidebar you'll also see the option to Emphasize popular ideas. If you check this box, MindMeister will highlight those topics with the most up-votes by making them bigger. This is a great way to see at a glance which ideas are the most popular among your collaborators.