What does Google do with all that data they collect on us? Most of it sits in massive data centers — quietly providing users with more “relevant” search results and news. But what happens when governments get involved?

That’s what Google’s latest transparency report provides — a detailed look at who’s asking for data and how much Google gives up. They even have an nicely arranged website for those interested in the stats.

The newest report was released today, detailing the six-month period of  July-December 2010. For curious individuals in the US — Google has received 4,601 user data requests from the US Government over the most recent six-month period and has complied with 94% of those requests (the highest compliance rate).

Other countries making full use of their information request power include: Brazil, France, the UK, and India.

The old adage holds true — “With great power vast quantities of data, comes great responsibility.” Good for Google for providing such a detailed and accessible analysis of this data.

We knew this day would come, if only because we saw Minority Report: A new NYC-based start-up, Immersive Labs, makes outdoor ads that scan your face as you approach and guess your age and gender. Combining this info with data about the weather and nearby social media activity, Immersive’s billboards then serve up the ad most likely to get your attention. They gauge success by measuring how long your eyes linger on the chosen ad. And the system gets smarter with each new passer-by.

While these ads raise obvious privacy concerns, Immersive Labs CEO Jason Sosa told the Huffington Post that they don’t save face-scans or collect any personally identifiable information. Still, one wonders how far companies like Immersive are going to take this. Right now, the ads just scan for age and gender, but might they one day add, say, race or body-mass index to that list? If they can pick up Foursquare and Twitter data, will they soon personalize ads based on data pulled from your mobile phone as you walk by?

Of course, targeted ads are nothing new — we’re used to seeing them pretty much all over the Internet. But Immersive’s ads raise the question: is there something about the very public nature of a billboard that sets it apart from other forms of targeting?