Geolocation apps and services like Foursquare, loopt, Gowalla, and Facebook's Places are an online-safety frontier where consumer (much less kid) usage is the great unknown. Thankfully, the Pew Internet & American Life Project has just released some research on it – on adult usage, anyway (hopefully youth data coming soon). Pew found that 4% of adult US Internet users use geolocation services to share their physical location with friends and find friends in their location and, "on any given day, 1% ... are using these services." Other key findings:

* Mobile Net users: 7% of adults who go online with their cellphone use a location-based service.
* Younger adults: 8% of 18-to-29-year-olds use these services, significantly more than other age groups.
* Ethnicity: 10% of online Hispanics use these services, compared to 5% of blacks and 3% of whites.
* Gender: 6% of online men and 3% of online women use location-based services.

[See also "Revisiting FB’s Places (& kids’ use of it)" and "Social location-sharing."]