In 2008 Valve announced that it would spend $10 million to promote their zombie co-op shooter Left 4 Dead. We are not sure if the game benefited from all that marketing and ad money (it's about shooting zombies with pals and it comes from Valve; copy sold for us) but the game was a big hit and continues to sell well in its PC Steam version.

Today Valve announced that they would be spending even more to promote the game's quick-to-develop sequel Left 4 Dead 2. How much? Try $25 million, which in case you are keeping score is over double what Valve spend to market the original game. Cue ad execs doing the happy dance now.

Look for print, billboards and online ads along with TV ads during UFC and Monday Night Football telecasts here in the US. Europe will also get a sizable push with TV, print and online ads along with more outdoor advertisements. Valve claims that Left 4 Dead 2 is already outpacing the original in terms of pre-orders sales, saying that the game has already set a company record for the most pre-orders for one of their titles. Valve's Gabe Newell is quoted as saying, "Left 4 Dead 2 has consistently run at 300% of Left 4 Dead's numbers." As usual for Valve specific sales numbers were not disclosed.

In related news the Left 4 Dead blog announces that the as yet unrevealed new gameplay mode for Left 4 Dead 2 will first be shown to the public during London's Eurogamer Expo on October 30-31. There is one hint given; the mode is 4 vs 4.