Prediction: PS4 to sell a minimum of around 70% of its lifetime sells in the first 2 to 3 years in the market.

[theprof00]

Either way, well, you're not far off from the truth. It's just that your numbers are wrong.
Consoles sell more in a bell curve over a 5-7 year period. It's games that sell the most in 30 days.
I think it's said that 50-70% of a game's total average volume occurs within the first couple weeks.
Consoles on the other hand are more like 50% in 2.5-3.5 years, with a good percentage of sales happening both at launch and at the mid-way point.
ie; sales will continue to slow, until japan launch, then christmas, then slow some more, then pick up at christmas, then there will be a price cut, sales will improve and imrpove until the midway point.