Nokia has bought the German web startup Plazes, a location-aware social network which lets users find out where their friends are and what they’re doing — a sort of “Twitter meets Google Maps” mashup.

It’s not yet known exactly how much Nokia paid for the service, or what they intend to do with it, but I wouldn’t be surprised if it becomes a part of Nokia’s Ovi service, pushing the company further into mobile services as well as simply making handsets…