The ITC is stepping in on the ongoing dispute between Nintendo and a company called Hillcrest. Last month, we learned that Hillcrest had decided to sue Nintendo over the Wii's controller, which they claim violates several patents that they own. Now the ITC will investigate to see if Hillcrest's claims are true.
Hillcrest demanded an injunction on the console, to prevent it from being shipped and ultimately sold, but obviously that has not happened (and is unlikely to happen). However, the ITC is the entity that can make import bans happen, so this is a sign that at the very least they are taking this case seriously.