At present, I can think of five sensor questions that involve Nikon at the moment:
- The D90 replacement. Even if the D90 replacement were to stay at 12mp (it won't), Nikon would need a new sensor here. State of the art has moved past the old 12mp Sony, especially where it concerns video. But where is the 60 fps, 14-16mp, state-of-the-art noise level sensor that's really needed to come from? Sony doesn't have one that I know of. Best guess: 16mp Sony-derived, 24/30 fps.
- The D700 follow-up. Is it a D3s sensor in the D700 body or is it something new? While I'm betting the former (and this would explain the D3s scarcity), there have been clear rumors of the latter. I don't believe we'll get both. Best guess: D3s sensor.
- The mirrorless choice. The speculation here has been on a smaller-than-DX, smaller than m4/3 sensor. Much of that speculation has come from lens patents, which show a 17mm image circle. One caution: some lens patents these days are getting filed at smaller, disguised sizes, and then scaled. If Nikon chooses a smaller sensor size, this introduces multiple issues. First, there is no third-party sensor of that size that I know of, so this would tend to indicate that Nikon has their own sensor planned. Second, it's unclear how Nikon would expect to compete with third generation m4/3 sensors and highly mature APS sensors on the other mirrorless entries. Best guess: If it's not DX with the D90 sensor, it'll be a new Nikon sensor.
- The D3000 follow up. Can we finally move beyond 10mp in the entry lineup? Sure, how about 12mp? ;~) Best guess: the old Sony 12mp standby goes into the bottom of the line.
- The D4 generation. The D3s and D3x set the bar really, really high. The D4 almost certainly has to have more megapixels than the D3s (or it needs to be non-Bayer at 8mp or greater). That's because the D3s seems to be "above the expected performance bar" for sensors as it is--I really don't see another generation of 12mp sensor with more high ISO gains in the making for 2011. Here's where I think Nikon needs to be with the D4 sensor: 16-18mp, D3 (not D3s) level of high ISO quality, 60 fps or higher frame refresh (Live View, HD Video), full pixel binning for video (no subsampling and interpolation on line data), 2k or 4k video capability with 4:2:2 color. Best guess: 16mp, near D3 level of high ISO quality, 24/30 fps, 720/1080P only.