Nintendo has simply grown too large for having so few business ventures. MS and Sony have enough sources of revenue that they can easily offset losses like those Nintendo are incurring over say the Wii U. Nintendo has few other products though.
That's why its good to see them branching out into mobile games and talk of movies.
Think of companies like Sony and MS as nice tall buildings but also wide near the base. Makes them harder to knock over during an earthquake (financial problems). Whereas Nintendo is a building just as tall, but unlike the others, got that tall without widening and reinforcing its base.
Especially in Japan, where the business culture is very different (it's way harder to switch careers or find a new job after losing one, and as such companies are expected to take care of their employees), Nintendo needs to branch out. If it turns out the kinds of products it makes don't have a place in today's market, they might have enough in their war chest to stay afloat while they adapt and change gears... which is basically what they're doing at the moment.
I hope it works, or a lot of people might lose jobs, which is probably why they're so reluctant to quit the hardware side of their business (the other areas of their company aren't enough to absorb their hardware staff).
