Last year’s contest must have been so successful that Valve has decided to use the photo contest again for this year’s advertising campaign for Left 4 Dead 2.

Just like last year, Valve is asking gamers to take creative photos of themselves in front of one of the outdoor media placements in New York, Chicago, Los Angeles, Seattle, Miami, Phoenix, Dallas, Minneapolis, and the San Francisco Bay Area. The entries will be judged by Gabe Newell and the top 25 entries will win a free copy of Left 4 Dead (probably the second although the press release just says Left 4 Dead) and one overall winner will get a custom engraved L4D2 Xbox 360.

“Last year’s out of home media campaign proved to be one of the most effective vehicles for helping land Left 4 Dead on 2008′s top 10 seller list in the North America,” said Doug Lombardi, vice president of marketing at Valve. “Valve has once again partnered with Gibson Media to execute the Left 4 Dead 2 out of home campaign and extend it to more markets across the US.”

To read all the details on how to enter go to www.L4D.com/contest