Ninja Gaiden's team hasn't discarded the possibility of making a Wii game.

In a recent interview, Team Ninja's producer and director Yosuke Hayashi had this to say about Wii:

"We would make something for the Wii if we came up with something unique that would only work on the Wii. There are several groups within Team Ninja. The PS3 group, the Xbox 360 group, and there are Wii fans in Team Ninja."

Given the fact that they're developing a Ninja Gaiden for DS, a Wii version is seeming more and more likely. Stay tuned for more on this subject.