Of course.

XDS: 200,000,000

Wii X: 100,000,000

But the NX is their next handheld

Depends on how their next home console and handheld console goes. If their next handheld is a hit like the DS line then probably within the next 20 years.

Never would be my guess.

By the end of 10th gen.

In a few more generations provided they don't wreck themselves

Also I am pretty sure the correct term should be "gaming devices" and not console if you are going to use that 700 million figure

For accuracy reasons,home consoles are at 275,98m(as of 27th of December) or 278.98m if we include the 3m of the first nintendo home console,color tv game(Only released in Japan) and handhelds at 404,62m(as of December 27th) or 447,62m if we include the first nintendo handheld console,game and watch!That's 680,6m or 723,6m with the first nintendo home & handheld consoles!:P

It'll be in my lifetime. If Nintendo makes decent hardware, they could own the market again. You'll have a one stop shop for Nintendo and 3rd party...just like the good ole' SNES.

I think there needs to be an agreed definition of console. I think annimportant defining criteria for a console is that its game library is not fixed and pre-loaded at the time of purchase. But others might have a different view.

I think I would be generous in saying that Nintendo may average 100 million console sales per generation for future generations. Assuming this is the best case scenario that means Nintendo will cross the line in the 11th or 12th generation. It's far from certain that there will be devices we can really call consoles that far into the future. I'm pretty sure there will be an identifiable 9th and 10th gen. But I have my doubts about consoles after that.

Will be a great feat if the achieve it.

Depends if they can get it all together, If their next hardware is a hybrid Home and Handheld unit it could sell more then the original DS did knocking of a good 157 million right there. If marketing is right that could happen by 2020. The it would take another iteration of this hybrid in the future to move them to the next level which might take another seven years or so putting them at around 2027. If the next console is not a hybrid and still remains a two tier system ,then the handheld market will be a lot stronger then the Home console market for them. In the home console only market Nintendo won't ever gain the momentum they had with Wii .. And with the 3DS at nearly the end of it's cycle and only hitting 60 million or so. I can not see Nintendo hitting DS numbers with anew handheld only. They will probably only get similar figures to 3DS as it's those owners who will upgrade. But i reckon the 3DS and Wii U have another 10 million sales left in them between them so that brings the number ever closer. But without a hybrid Handheld / Console system Nintendo may have to wait for a very long time to see the 1 BILLION MARK. With the hybrid system they could change gaming forever and surpass the 1 Billion Mark by a mile.. It's in your court Nintendo.