If mobile phones managed to half how many Nintendo handhelds get sold from generation to the next, what do you think will happen in the next one?

At the very least there actually will be a next gen handheld from Nintendo. 

Where else can they go? Their next console's future is looking shaky.

As he said, they just need to deliver a high quality value for people to go there. That basically mean more games, because phones and tablets, while beein gable to deliver games wont ever be able to deliver the controls and fidelity of a console experience. Mobile games are shallow by deifition so they can be sold at a cheap price. They will never be able to completely replace portables. At least not with that kind of software and pricing model.

That´s a rather silly question, since Nintendo isn´t that desperate to call the console market dead and shutting down prestigous studios like "Studio Liverpool" that work on there consoles, on the contrary they are starting to focus on WiiU right now.

I came to another conclusion...Sony hurt themeselves really bad with PsVita.
3DS is doing fine considering it had a bad start, also it's true the 3DS is selling less than the original DS but you'll also have to consider DS sales were unprecedented even for Nintendo handleds thanks to games like Nintendogs and Brain Age.

Studio Liverpool made the mistake of not evolving.

This explains Sonys focus on indie games especially when it comes to PSV.

Care to explain?

It was sarcasm because "not evolving" wasn´t the reason they were shut down. It has more to do with Sonys opinion about their handheld market (PSV).