Currently the Omni Admin sees:
[any community you created or belong to]
This adds a lot of unnecessary clutter.
I think it should rather read:
All Site Administrators
For non-Omni Admins, currently it lists all communities which you have created. I think that's good for when you access Announcements from the "My Home" view, but if you're already in a Site you should only see that site OR at least auto-select that site by default.