Steam weekly top sellers, May 31 - TF2 tops with Orange Box still going

Valve has announced that it will start publishing a weekly list of the best-selling titles on Steam.

Bout time.

Updates will arrive every Sunday, and you can see the very first one below.

Steam Weekly Top Sellers - WE May 31

1. Team Fortress 2
2. Killing Floor
3. Left 4 Dead
4. Counter Strike: Source
5. Plants vs Zombies
6. The Orange Box
7. Unreal Deal Pack
8. Unreal Tournament Black
9. Assassin's Creed: Director's Cut
10. Call of Duty 4: Modern Warfare