What he said. Not to mention the Wii-U disks and games may have crazy encryption like MGS3 preventing anyone from hacking it.
I don't mind if it can't be hacked, it's still a whole new game and chances are, it's gonna be better than Brawl so I'd rather go the next step than stay here, besides, it's not like I can't go back to Brawl every now and then like I do with Melee.