Lol ps4 numbers.
It's not "It's like one month of great sales", it's based on history, price and market analysis. I have explained in detail, if you bother to read it. But of course, you seem to be on the other camp, so I don't think you'll be willing to go through all that pain. But as a quick summary,
PS4 will definitely do better than a LATE, EXPENSIVE, DEVELOPER UNFRIENDLY CONSOLE, WITH BAD MEDIA COVERAGE. Anyway you may wanna spin it, the history tells us that it will sell past 100+ million. However, that's not just it. There is no mighty Wii this generation. Also the Xbox is doing a lot worse everywhere, and as of now, there is not one single country it is leading, not even in US. This is not just a coincidence, but evident from the huge demand for PS4. Also just take a look at the history to learn that the more expensive console never has a chance in US. So forget about an Xbox victory in US, never gonna happen. All that brings PS4 sales estimates way past 100+, easily surpassing PS1, and closing to the PS2.
Another thing people forget is that PS2 sold 140 million in around 5 years. PS4 has 7 years to catch up. So it doesn't have to sell that fast. Also the market is larger now, making its job way easier. So PS2 levels of SALES NUMBER is within reach. However, that kind of MARKET SHARE is a tough DREAM.
Regional Analysis (only MS and Sony Consoles)
Europe => XB1 : 23-24 % vs PS4 : 76-77%
N. America => XB1 : 49-52% vs PS4 : 48-51%
Global => XB1 : 32-34% vs PS4 : 66-68%