How can I ensure that I'm logged out of Google Latitude?

When in Google Maps, when I go into the menu, I see "Join Latitude" option next to Latitude icon. When I am on Google Latitude web site, it tells me "Location sharing is not turned on" Does that mean that I am 100% logged out of Google Latitude? The reason I ask is that I was experiencing major battery drain via Google Maps, and many people on forums heavily recommend signing out of Latitude as a solution. However, it seems that my Latitude is already off.