To check-in, or not to check-in? 

This was one of many questions asked at an entire day of geolocation-related talks at the USC Davidson Conference Center Tuesday for Social Media Week Los Angeles (SMWLA).

Geolocation—the ability to broadcast your whereabouts to others via cell phone or Internet—is the tech topic of the moment. Why? The location-based market is estimated to be worth up to $4.1 billion by 2015. Preemptive marketing heaven.

Location-based advertising used to be subtle: find where consumers are, then strategically place ads. Movie theater pre-previews. Roadside billboards. That sad, sweaty sign twirler on the corner wearing a foam Statue of Liberty crown.

But soon, ads won’t have to find you. You’ll decide which ones you want based on where you decide to check-in.

True, geolocation is still in infancy, but not without a hefty cult following on Foursquare, Gowalla, Whrrl, Yelp mobile, and many, many others. Facebook Places opened the market to its 500 million users recently, but of course, many still haven't jumped on the hey-everyone-look-where-I-am bandwagon.

But this will soon change, said Rob Reed, CEO of MomentFeed, a company that helps other companies implement location-based services.

“Ultimately, location is going to fade into the background,” said Reed, who hosted the SMWLA geolocation conference. “It’s not going to be that novel, just like we take for granted that so many applications now have social [features]."

Already, nearly 40 percent of cell phone users take advantage of some form of location service on their device. This statistic is expected to grow, and grow. And advertisers have a whole new playing field at their disposal. Literally.

The explosion of Web marketing in the 90s created “clickstreams,” a new way to drive ad placement based on clicks. Now, the hot new data is known as “footstreams," noted John Kim of Pelago, Inc., the maker of Whrrl.

In other words: your real-world digital footprint. An advertising gold mine.

Screw Ads, What About Me?

Advertisers aren’t the only ones who may benefit from the explosion of location technology.

Geolocation is based on real physical places. It may be the missing link that would make social media actually social. By nature, staring at a screen isn’t much of a tactile, interactive human experience. Sorry, FaceTime.

If check-ins become integrated with cell phones to the point that meetings, social gatherings and other face-to-face events become easier and more frequent, the future of the Internet may not be so terrible, after all.

Geolocation promoters say that this may be the best way for technology to serve local audiences. Speakers at the SMWLA event touted personal benefits such as neighborhood networking, community-building and connecting with fellow event-goers.

How?

Services like DeHood offer both public and private ways to network with your neighbors about local news, community events, food and ways to meet new people.

Companies like DoubleDutch help event planners create location-based mobile apps to connect users around a specific event, just like the Social Media Week September 2010 app.

Perhaps one day, birthday parties and family dinners will have a one-click app that stores and organizes all RSVPs, photos, comments and potluck lists. No one takes Facebook Events seriously anyway, and this could be a much-needed replacement.

But Where in the World Is Carmen San Diego’s Privacy?

Fictitious criminals aside, privacy is one of the biggest challenges geolocation providers face.

Earlier this month, German residents made a big statement when hundreds of thousands of tenants opted out of Google Street View.

PleaseRobMe.com points out the dangers of over-sharing location information, such as home burglary.

On the other hand, services like Brightkite allow users to set privacy levels per check-in, as opposed to a one-size-fits-all privacy setting (coughcoughFacebookcoughcough).

But the burden of public safety shouldn’t be placed on the shoulders of location service providers. What kind of free-thinking society would we be if we even wanted them to control our well-being? Maybe self-help bookstore sections would shrink, but that's no incentive to hand our lives over to rulers of the Web.

At the no-brainer level, there are obvious safety guidelines for navigating the location-happy future of social media: Don’t broadcast your home address. Keep your out-of-town absences private. And no one cares about your hangover. Not even your hangover.

Over-sharing seems to be the biggest problem in this arena so far, but fortunately it's primarily a user-created issue. Maybe real estate agents will begin to quip, "Education, Education, Education" as we enter the next phase of social media evolution.

And as it stands, all geolocation services are currently optional, meaning that users check-in because they want to. Those who opt out remain delightfully MIA as far as they're concerned.

As far as you know, I’m writing this from the capital of Antarctica.

Reach columnist Lisa Rau here.

Follow her on Twitter: @LisaRau

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