Germany’s Der Spiegel published an interview with Twitter CEO Evan Williams yesterday on its website, and Williams had a couple of interesting things to say. You can find a poorly Google-translated version of the interview here, which features Williams answering the usual, boring questions ‘professional’ journalists tend to ask about the micro-sharing service (the reporter opened the interview with the Pulitzer-prize caliber question “so does Twitter spark narcissism and idiocy?”).

But Williams did share something worth noting at the end of the interview.

When asked about possible future features for Twitter, he reportedly said that one of the things being considered is an extension that lets people know what’s happening in their immediate vicinity. That would basically mean that Twitter could actively ping users about local events that are going on in their neighborhood, in real-time, based on the location they’ve indicated. As an example, Williams says users could be alerted to the fact a fire is burning a few streets away from where Twitter knows (or thinks) they are.

It’s not clear if this feature is under development or merely in the idea stage right now, but rarely does anyone from Twitter give so much insight into the startup’s plans for the future in terms of product features, so we’re inclined to believe it’s coming sooner rather than later.

Some questions arise. How frequently would Twitter ping users on local news? In what form (replies, direct messages, SMS, …)? How personalized would this be (what constitutes news for you may not mean the same to your neighbor)? And if it’s only about alerting people in case of emergencies, like the example Williams cites, who would be the one to determine when and why it’s worth sending warning messages out to users? Would they be possibly opening such a feature up to the authorities (police, fire fighters, etc.) so they could be the ones alerting users about potential risks in their vicinity themselves?

Last but not least, could this be an indication of their impending revenue model? If you think about it, location-based marketing messages would fit right into all of the above, for better or worse.

(Hat tip to TechCrunch blogger Serkan Toto)