tedster - 10:19 pm on Jul 4, 2010 (gmt 0)
It's pretty easy to opt out. From the same page:
The first time you go to a Web site that requests geolocation information, Google Location Services' terms and conditions are presented. If you agree to them, the service is activated,
After that, every time a Web site requests geolocation information, Opera tells you, and gives you a choice: to send your location data, or not to send it.
If you at first reject Google Location Services' terms and conditions, but later change your mind, open opera:config, search for "Enable Geolocation", check the checkbox, and save the settings.