Corners of the PR field are getting curious (and excited) about social media sites that embrace geo-location and GPS to insert "where" into networking. Sites like Foursquare, Gowalla and Loopt rely on users giving up much of the location anonymity they previously enjoyed in order to plant digital flags (check-ins) in places like coffee shops, bars, stores and just about anywhere else people gather or visit.

Twitter played a key role in the developing craze when, at the height of the media frenzy embracing the microblogging service, it began rolling out a geo-tagging service last year which enables users to indicate the lattitude and longitude of "tweets." The SXSW Digital conference last month set the trend ablaze.
The space is so hot now that the Wall Street Journal wondered last week if start-ups will fall victim to "check-in fatigue."
So with sites like Loopt, Foursquare and Gowalla on fire of late, what does it mean for a PR field already sprinting alongside the social media train?
The implications are more obvious for businesses like restaurants or retailers that rely on a local base. Frequent visitors on Foursquare [the top visitor to a locale is known as a "mayor" while users earn "badges" for various activities] can be embraced or queried by businesses as any "influencer" would traditionally be approached in PR.
As the Miami Herald tech columnist Tasha Cunningham asked, "Wouldn't it be great if there was a way for you, as a small business owner, to send messages directly to customers when they're blocks away from your location?"
Here are five brands that have embraced location technology to create some simple but interesting PR and marketing opportunities:
1. Zagat - teamed with Foursquare, the restaurant review powerhouse created a "foodie" badge with its "Meet the Mayor" series.
2. Tasting Table - Loopt, a competitor of Foursquare with more than three million users, countered the Zagat deal with its own partnership with Tasting Table to show the dining review site's content to Loopt users.
3. Adobe - the software developer and marketer has partnered with Gowalla to place "stamps" around the country that can be discovered when users check in at the location. The stamps are redeemable for Adobe software. Food chain Chipotle is deploying a similar program.
4. Bing - Microsoft's Google challenger is adding Fourquare results to its maps providing searchers with reviews and tips from the social network.
5. The North Face - a location-based twist on doling out coupons, the outdoor retailer tapped a "geo-fence" system to give out coupons via a virtual perimeter that sends a text message coupon or promotional message to someone who steps in the zone.
6. Starbucks - setting up a type of location-based customer rewards system, the coffee house chain created a Foursquare "barista badge" to reward frequent visitors.
7. New York Times - kicking off an ongoing partnership, the paper of record worked with Foursquare to create badges at the recent Winter Olympics in Vancouver and share content on local eateries and attractions.
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