I'm shaking my head. First of all, Sony admitted they are still losing money on the PS3, and Kaz said it might take until the end of 2009 to turn a profit on it. Thus selling another 25 million systems (12 million sold so far, subtracted from the less than 40 million according to the chart), would hurt Sony a lot more than it would help the PS3's marketshare.
Second of all, I question why the PS3 will climb, but the Wii will level out. There is no actual justification for that in the actual article. It just seems to be a way to insist the Wii still won't win.
Not that the Wii has to win, but just the idea that the other systems are somehow going to catch up. There is little to indicate that here. The games are selling, but the fact is that the Wii is selling out, and still beating them. Assuming either system could top that needs some kind of damn good reason for that. There isn't any now.
BTW, this isn't bashing any system. It's just stating that a prediction like that doesn't make sense, based on current information.