Once the price is affordable for the average consumer and if they manage to thoroughly market the all in one entertainment box to the general public, you could see 60 - 80 million in North America alone. Ps4 will kill it in Europe/Japan/Other, but once the price becomes parity, unfortunately, it will surpass PS4 in North America. Overall I think Xbox One will top out at 120-130 Mill worldwide vs PS4 150-160 and Wii U 100 - 120 ( never count the big N out!). I truly believe we will see massive growth this gen as well as a longer generation than what is predicted.

55 Million. This gen will be down overall compared to Gen 7.

It's mostly guessing(unlike with the Wii U, and even PS4:one is bomded already(x1 probably awaits the same fate) the other one is leading all the way), but most likely result is ~50 mln.

Around 140 million.

21 million.

Microsoft is in a weird place right now as a company and ditching a failing console soon after launch is something the new management could do. XBOX is spun off and their first act is to make a successor. Hence the sales are cut short.

That's 3.5 million this year, 7.5 next year, new system announced and 4 million in 2015, and 6 million in the following years after being replaced.

I'm just going to toss a number: 110 Million

I think 60-70 million. Last time it had a one year head start and some very weak competition from the PS3. The fact that it's launching with a cheaper and more powerful console is going to hurt it.

I think the new architectures will change our concept of generations and ongoing will be binary compatible scaled architectures. I honestly thought (hoped) that MS would have just scaled their PPC arch for the next gen, but I can see why they went with x64 arch.

45 to 50 million console systems.

29 million