http://www.theage.com.au/technology/technology-news/please-explain-why-google-wants-your-wifi-data-20100513-uyyh.html

The letter comes in response to recent reports that the company has been quietly collecting Wi-Fi data around the world when taking pictures of streets and houses for its mapping service.
Street View, which has already rolled out in a number of countries including Australia, displays panoramic street-level photos taken by specially equipped vans which are also equipped with Wi-Fi receivers that scan private network signals as it drives through neighbourhoods.

Sans doute deja dit, mais j'etais pas au courant.