I never really saw the Sensor Plus pixel binning as a competitor to Canon/Nikon as much as it provided an alternative.
Hi Steve - This is true enough today. But I have a feeling as N&C improve their per-pixel performance, the ability to bin pixels cleanly will figure more prominently in their strategies. For example, the D3x makes a pretty damn good low light camera that compares favorably with the D3 (but not the D3s) IF you downsample the 24.5mp files to 12mp judiciously.
In other words, I'm not putting bets on Nikon necessarily continuing its "low pixel/high sensitivity" versus "high pixel/low sensitivity" cameras strategy. Then again, the odds of them doing anything to alienate their Olympic shooting extravaganza photographers is next to zero, so they'd have to really deliver on performance.
But binning and sensor+ technology looks increasingly attractive to me these days. The cleaner the per pixel performance, the more a downsampled capture from a small-pixel camera can demonstrate the same benefits as captures from a large-pixel camera (where the sensor area is held constant).
There seems to me some reason to try to provide medium format cameras that are capable of handling fast action in low light, and they could produce through downsampling/sensor+/what-have-you results that would exceed the 35mm DSLRs even in low light situations. Give me an S2-sized body at max D3x prices, with a large sensor, fast capture streaming, CMOS, and able to switch roles depending upon what's asked of it. I'll be yours for life. And BTW, I've seen some models who can deliver 5 killer poses per second. [My pet theory is that the nerdy models deliver more cool facial expressions per second, and that theory is worth a laugh anyway.]