Some time ago I tweeted my concerns that despite Google Android asking whether consumer would like to enable Location Sharing (opt-in) during the initial device setup, one still had to manually disable location sharing in Android's web browser - this is enabled by default even if you don't opt-in to location sharing during the initial device setup. This, in itself, is enough to stifle Google's claim about Android location sharing being Opt-In.
However, to make matters worse, when you install an Android update (as I did with Froyo and soon will again with Gingerbread) it reverts the browser setting for location sharing back to "On". This is completely unacceptable and only now (after several months) have I noticed this because one assumes that once you disable it, the setting will persist. It is only because the issue came up again today that I checked my browser settings, to find that it had been "on" for several months.
Furthermore, it has been reported that the Android Twitter Client also reverts location sharing back to "on" when it is updated.
I would advise anyone who has an Android device and does not want to disclose their location to the world and his dog, to go into any net facing apps (including browser and social networking clients) and check that location sharing is turned off.
I will be discussing this with Google over the next couple of days "suggesting" that this is dealt with before Gingerbread is released by making the default option for the browser and other apps set to disable location sharing - either that or the initial setup where one can "opt-in" to location sharing needs to persist across ALL applications including the browser and social networking apps. I will post updates when they become available.