There are new social networking applications everyday, but Brightkite has managed to differentiate itself slightly on iPhone and Android by incorporating location-based services.

Mobile-Ent.biz reports that a deal has now been struck between Brightkite and US retail giant Best Buy to bring one of the first examples on in-app augmented reality advertising.

The new ad campaign is on a one month test over the Christmas period, and points the way toward Best Buy stores and relevant, real-world products. Augmented reality advertising is an unproven entity so far, so it'll be very interesting to see user's reaction to the new system.

Advertising is one of the areas expected to drive augmented reality, so advertisers and developers are expected to be watching this experiment very closely.