Google is planning to allow users worldwide to opt-out from their Wi-Fi hotspot location database later this fall. The announcement, made on the search giant's European public policy blog, is surely a response to legal troubles the company has encountered after it was revealed that the process of mapping these hotspots also captured information about individual Wi-Fi devices like computers and smartphones. Google has also run into legal trouble when the company admitted in 2010 that it had inadvertently intercepted fragments of data being sent over the networks it was mapping. The information in this database allows Google to estimate the geographic position of a user based on the known positions of Wi-Fi hotspots. Early iterations of the iPhone determined location in the exact same manner, using a database from SkyHook. To create their own database, Google's streetview cars were equipped with Wi-Fi sniffing sensors that mapped the location of every wireless device they came across, as well as some they didn't intend.

Microsoft has apparently been gathering location information for wireless devices and publishing it through their Live.com API. The API data contains the location of cell towers and Wi-Fi hotspots which can be used in locating a mobile device nearby -- similar to how early iPhones operated. However, CNet reports that buried amongst the benign information are the MAC addresses of other wireless-enabled devices, which could include phones, computers, and more. To build their database, Microsoft has been drawing on information "crowdsourced" from Windows 7 Phones and by special vehicles with Wi-Fi sniffing antennas. Does this sound familiar? It should. Cast your mind back a few months to a time when the world looked scornfully at Apple for "crowdsourcing" the location of Wi-Fi hotspots and cell towers across the country through the iPhone. And just a few short days ago, Google faced similar allegations; that they're Street View cars were also used to gather wireless access point information and may have posted user's MAC address online. If you throw the two of those together, you more or less get what Microsoft has been up to. Responding to CNet's report, Microsoft says that it only publishes the location information of Wi-Fi devices it knows to be stationary. Presumably, this is done by comparing the data taken over different days. However, it seems that some wireless devices could have slipped through this filter.