By PETER WYLIE, special to LTW

Editor’s note: Local Tech Wire asked Peter Wylie for his reaction to Facebook’s changes in privacy policy this week. Wylie is a researcher at , a social media marketing company in Raleigh, N.C. He was previously an editor for an online business journalism company in Washington, D.C.

RALEIGH, N.C. – , the latest Web wonder, closed recently on a $20 million round of venture funding. The start-up brushed off acquisition offers from Facebook, Yahoo!, and other companies to try to build a viable standalone business.

Foursquare has gotten more media attention recently than almost any other new social technology, but Foursquare’s small user base currently makes it relatively insignificant for marketers trying to reach their target customers.

The functionality of the service is limited, and it has yet to show any promise for businesses other than restaurants and bars.

So why should marketers care about the additional funding the company received? It’s a matter of scale, the market, and the potential.

The service, which allows users to “check-in” at local establishments and see where their network of friends are “checked-in,” currently has 1.8 million users, mostly clustered in the Top 20 metro areas in the U.S.

The new financing allows the company to add features and capabilities that could help it to scale rapidly and become a useful tool in a marketer’s toolbox. Foursquare was founded in March 2009, and has since attracted users at a faster rate than the other two social giants, Facebook and Twitter, had at this point.

As the image [with this post] shows, both Facebook and Twitter experienced most of their explosive growth after drawing down their first significant round of funding. If Foursquare can produce similar growth now that its coffers are full, the fledgling social network could become a very powerful marketing tool.

Marketers who learn the interface of the system and how to interact with users now will be at a great advantage to those who have to figure Foursquare out once it’s already a giant. Funding allowed Facebook and Twitter to grow their staffs and add features to the service that attracted users, and Foursquare will follow suit. It also has the advantage of a focus on producing business value earlier than the other services, which only evolved a business focus once they had achieved critical mass.

There is absolutely no guarantee that Foursquare can achieve the prevalence of either Facebook or Twitter, but all of the initial indications point in that direction.

Savvy marketers who want to hedge themselves against Foursquare taking off should set up a personal and company profile to begin familiarizing them with the service and its capabilities.

It’s a very low time commitment to do so, and if the past growth patterns of other major social networks are any indication, there is a significant opportunity on the horizon to attract future customers through Foursquare.

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