Silly lawsuit.
Apple can't sue Microsoft because Microsoft made an OS after they did or vice versa.
If someone else does the same thing in a different way, you can't sue them for it. Nintendo need not even bother with this. They only need to prove that they didn't steal their design (which they probably can, they're a big company and they probably have records detailing how they designed the Wiimote). The only thing they should do is hire someone to sit on their ass in court (if they don't want to go themselves) while the court decides the lawsuit is stupid.







