20M is doable

i will say no

What???

Ok, maybe i'm much octimist with PS4, but you really think that PS4 lifetime don't will outsell XBOX 360?

XBOX 360 will sell 87.5m lifetime, MAXIMUM 90 million, so, PS4 will sell less than 90 million? :/

Maybe not that low, but the PS4 isn't doing 25m in one year. It's "hype sales" are already gone. Doesn't mean it won't sell well, but it won't do 24m-in-one-year well. Maybe 80-90m life time. 

Lol bro PS4 will sell that much lifetime. Just kidding but I think it's peak will be around 11m, maybe 15 if it gets lucky like the Wii. Lifetime around 75-90m

So, you think that LIFETIME PS4 will sell less than PS3?

PS3 will sell minimum 90 million, my prediction is 92.5 million, so, if PS4 will sell 80-90 million, will sell like or less than PS3?

Only question: WHY!?

PS4 will sell MINIMUM 100 million.

ps4 will not only sell less than 90m,but also less than its predecessor...gaming section has shrunk  and it has to cope with japan s ignorance!75-80lifetime

I really don't think so. It would take something really huge to push it past 90 million. The only three consoles that did that were cultural phenomenons. I don't think the PS4 is that product.

No way. It will have to sell an average of 2m a month to sell more than the Wii.
Your 170m PS4 lifetime prediction is more ridiculous though.

Yes, i agree, the PS4... no, the all migthy PS4 will outsell every other console in history and become the saviour of gaming. Wii sold 24 million in 2008? The PS4 will do that in one month reaching sales of 1.2 billion by the end of 2015.