I'm going to be wrong and say Nintendo. EA, Ubisoft, Activision and the gang are all financially secure, as fer as we know. We might not like them, but they have franchises that print money, no matter how stale they are.
Nintendo has more of these franchises than anyone, but they don't know how to make a new console anymore. The Wii was a buffed up Gamecube and the Wii U, while all new, uses antiquated hardware and costs a lot more than it,s tech justifies while losing money on each unit. Personally, I think after the next (post Wii U) generation occurs Nintendo will truly be a dead company walking, and instead of playing it smart like SEGA they'll give it one last Atari-like hurrah, killing the company in all but name.
Of course I could be wrong about Nintendo's next console, and will almost certainly be wrong about them being next. Another publisher will fall between then and now, but no one can know who that will be.