Gabe Newell confirmed Valve’s interest in the Wii U console while speaking at the Games for Change Conference in New York. Newell seemed encouraged that the graphics and CPU performance would make the console fit into Valve’s scalability model.
If Valve does choose to support the Wii U, it will be the first time that Valve titles would appear on a Nintendo system. While Newell did not confirm if Valve has anything planned yet, it would appear that the company is at least looking at the possibility going forward. There is a question of how well the Valve titles would do on the Nintendo platform, but that question can only be answered if they end up releasing titles for the platform.