Xbox One DRM/unveiling/PR disaster, no doubt. So bad, it even overshadows failures like Wii U sales, PlayStation Vita, SimCity 2013 and even Electronic Arts' ongoing troubles.
So bad that, to this day, many months after the smoke has cleared, you still have forumites calling the machine "Xbone" as an insult. And it's still funny, dammit.
One thing I will say, though - this year, there was plenty of industry bullshit for gamers to get up in arms about. When you think of how it could have been...*shudders*