The colored dots in the visualize priority plot map help you identify which ideas are the most fresh and which ideas are the most fleshed out. They are based on the assigned impact & effort on each idea.
The size of the dot determines how detailed the idea is, essentially a rough guide to show you the difference between a one-liner and an idea that has a bunch of comments, mockups, user stories, etc. It's by no means scientific, but useful to have a rough idea!
The color of the idea determines the last time they were updated, ranging from bright pink for ideas that have been recently interacted with, to a plain grey for those that have been ignored for a while.
The color of the idea determines the last time they were updated
If you toggle on the 'confidence' view (currently in beta), the colour of the dot will relate to how confident you are in the success of the idea