The Steam store now has a top 10 RSS feed for Steam Weekly Top Sellers based on revenue for the week, updated every Sunday.

This weeks top 10:

1. Left 4 Dead
2. Killing Floor
3. Assassin's Creed™: Director's Cut Edition
4. Team Fortress 2
5. Unreal Tournament 3 Black
6. Penumbra Collector Pack
7. Counter-Strike: Source
8. Unreal Deal Pack
9. The Orange Box
10. Freedom Force: Freedom Pack