"Though it comes a mere one year after the original, Left 4 Dead 2 is a much better game and much better value. The new campaigns and unique game modes offer more variety and more longevity, while all the other additions and tweaks make the already great gameplay even more enjoyable. [...] Though the core gameplay remains pretty much the same, there is more than enough new content and improved action to make this zombie apocalypse highly recommendable."
In comparison, GameSpot awarded the first Left 4 Dead an 8.5 out of 10. 9.0/10