Funny what happens when you're the developers behind Red Orchestra and you go and release a new game about zombies. Your game goes to #1!

Yes, Tripwire's Killing Floor has maintained its run at the top of the Steam charts, strong pre-sales from preceding weeks continuing into strong sales now that the game is actually out.

As for the others...NPD is boring, as usual, while the DIrect2Drive charts are really starting to grow on me. Or, should I say, Direct2Drive customers. Mount & Blade at #1? What an amazing group of people.

NPD Charts May 3-9 (via Shacknews)

1. World Of Warcraft: Wrath of the Lich King
2. The Sims 2 Double Deluxe
3. Left 4 Dead
4. World Of Warcraft
5. World Of Warcraft Battle Chest
6. Empire: Total War
7. Spore
8. Fallout Trilogy
9. Bejeweled Twist
10. The Sims 2 Apartment Life

Steam Charts As Of May 19

1. Killing Floor
2. Call of Duty: World At War
3. Left 4 Dead
4. Plants vs Zombies
5. Team Fortress 2
6. Counter-Strike Source
7. The Orange Box
8. Call of Duty 4
9. Empire: Total War
10. Battlestations Pacific

Direct2Drive Charts May 10-16

1. Mount and Blade
2. Sacred 2: Fallen Angel
3. Battlestations: Pacific
4. Civilization IV: The Complete Edition
5. Civilization IV
6. The Sims 2 Double Deluxe
7. Mass Effect
8. Neverwinter Nights 2: Mysteries of Westgate
9. Fallout 3
10. Elven Legacy

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