Pumpkin Spice Latte fans, your challenge starts now to get the drink first in your city.

Starbucks launched a Facebook competition earlier today to let fans vote on which city the coveted drink should be sold a week earlier than the rest of the world. The contest ends Thursday.

The promotion is another example of how companies are increasingly turning toward social networks to promote their products -- and how social networkers seem receptive to the idea -- especially when done with a light touch.

Over the next four days, fans will play four games on the Facebook application -- ranging from a video trivia game to a picture hunt -- to earn their city points. The more fans play, and get their answers correctly, the more points they earn. But, you can only play each game once every four hours.

As of 11 a.m. ET, Chicago was in the lead with 58,500 points followed by New York City and Boston.

The promotion seems to be working:  fans are posting their support for the drink on the page’s wall.

Pam Martin, of Jackson, TN, said Starbucks should bring the drink there first because life there is “boring...please bring that one small ray of light for us!!” Christian Gaucher pleaded the drink should be debut in Groton, CT first as “noooothing good ever happens here.”

Other fans are even planning -- or at least contemplating --  a carpool to the first Starbucks to be one of the first ones to get the drink. Maggie Paparella, of Exton, PA, is one of those fans. She wrote “we are going to carpool a group of PSL supporters to the first Starbucks in Exton.”  

The application is also tracking “Top Contributors,” i.e. who are playing the games, more often and are earning the most points. Being the application is just a few hours old, the top five leaders all have 11,500 points each.

Other food brands have tapped into their Facebook communities to get fans excited about their products.

McDonald’s, which introduced new dipping sauces for their chicken nuggets, has a game called “McNuggets Saucy Challenge” where fans dip nuggets into sauces and earn points.

Dunkin’ Donuts, a fast growing competitor to Starbucks, has a competition on their Facebook where users can become the president of Dunkin’ Donuts if they check-in frequently.

Facebook members seem to be responding eagerly.

Photo by emilyonasunday