Here are the ten top selling titles on Steam for the week as reported by Valve:
1.BioShock Infinite
2.Arma III
3.BioShock Infinite Season Pass
4.Defiance
5.Grand Theft Auto Complete Pack
6.Hitman Absolution
7.Grand Theft Auto IV: Episodes from Liberty City
8.Kerbal Space Program
9.Just Cause 2
10.Age of Empires II HD Edition