This is a pretty big case to watch. Are there any cases of emulators being sued successfully? A user being able to provide keys and a rom from which they could own or be homebrew doesn't seem to violate copyright to me. edit: seems the consensus is once via legal fund attrition, but the case went to the emulator authors in the end.
bleem! (PlayStation emulator) was sued by Sony and was forced to close down because of legal fees, so I guess that counts as a success for Sony. I seem to recall a bunch of ROM sites disappearing as well, but not sure if that's because they got sued or for other reasons. Some must have been sued and consequently shut down, so maybe not a bad idea (for the companies) to at least try?
The only 'emulator' cases I've seen be successful are due to the same, they didn't get in trouble for the emulator, they got in trouble for distributing ROMs. I wonder if there's some firmware code being distributed here? that's a common annoyance when it comes to using an emulator.