Or by clicking a switch in system settings. Explanation for those outside the Ubuntu bubble: 12.10 has had an Amazon search integrated into the main Unity lens

Or by clicking a switch in system settings. Explanation for those outside the Ubuntu bubble: 12.10 has had an Amazon search integrated into the main Unity lens, and this is enabled by default. Early in the release of 12.10 a graphical 'kill switch' was added to system settings. Before that, you had to uninstall a package manually from the command line. As I commented up the screen, I hope Canonical don't alienate their users with (any) more of this sort of thing as switching between GNU/Linux distributions is relatively easy.