At this point Canon just needs to concede defeat and us the Sony sensors.
Given Sony's financial struggles (particularly the Moody's downgrade), I can imagine a scenario in which Sony sells off its imaging division in order to stay afloat in other areas (TVs, computers, phones, etc.). I wonder if Canon might consider buying Sony's imaging division and/or patents. That could be exciting. Although, the downside is that there would be less pressure on Canon to innovate, so we'd get the short-term gain of Sony's current sensors, but could that be at the expense of long-term innovation/competition?
It'll be interesting to see what happens. My guess is that Canon is always working on new/innovative sensor tech. Whether/when we see it, of course, depends on effectiveness of the tech, reliability, production capability, competition, market conditions, et cetera. Canon may move slowly, but I'd be very surprised if a significant jump in sensor performance doesn't come along in the next 1-3 years.