It depends when it declines. But after 2011 we'll likely see new consoles from somebody - Sony will be eager to go first if they're dealing with two Wiis (Wii / Kinect), and two DSs (DS / 3DS). Nintendo will be ready if Japan starts to collapse completely for Wii, or if price cuts / seasonality stop working. Microsoft will be ready if Kinect doesn't have legs or only works in USA / UK / Australia / Canada to boost hw.
By end of year we're looking at something like 84m Wiis, 50m X360s, and 47m PS3s. My impression is Move will cannibalize X360 further in Continental Europe and X360 will continue declining in Japan during 2011. Kinect will cannibalize PS3 in the USA / UK / Australia / Canada. So for 2011, Wii / PS3 will be close in Japan, Wii / X360 will be close in Americas, and in EMEAA various countries will have Wii and X360 close OR Wii and PS3 close, with Wii winning by a bigger margin overall since EMEAA preferences are split.
Let me get this straight...
You think the PS3 will outsell the 360 by around 1.2m in the next 4 weeks?
This means you expect the PS3 to sell 3,779,506 in the next 4 weeks (best so far 2009 - 3,311,658)
and you expect the 360 to sell 2,633,855 in the next 4 weeks (best so far 2008 - 2,726,639)
That would be the best performance for the PS3 by approx 14% up, despite it tracking a tad lower than 2009 at the moment. You are further saying that the 360 will fail to match its 2008 performance for the coming 4 weeks, depsite it tracking higher at the moment (in the last 4 weeks the 360 managed to outsell 2008 by 500,000)
I'm very confused.