One of the unique features of Count.It are the "public" leaderboards. These include the World leaderboard, and leaderboards for many of the towns and cities around the world. Choosing to be "public" allows any group to see how they compare to other groups in their region, or in the world. Users can also choose (or not!) to appear on public leaderboards. To toggle your group privacy preferences, go to your Admin --> Group Profile page.
To break it down in detail:
Public: The group will appear in site search results and on public leaderboards, and the group homepage will be visible to other registered users of Count.It.
Private: The group will not appear on public leaderboards and is not searchable on Count.It, nor is it visible to other Count.It users.