Many folk get all religious about sensors. Obviously, sensors are at the core of our cameras, so it's probably right to think of them as a key technology that drives our imaging process.
But we also get carried away with this thinking. For example, the Sony fan boys get all exited every time Nikon uses a Sony Semiconductor supplied sensor, apparently because they think this validates their choice of a Sony camera. That's a bit like saying that Windows PCs are great because Macs use Intel processors.
I mention this because a comment I got pummelled on earlier this year has now proven to be accurate: the D3200 does not use the common 24mp Sony sensor. It uses a Nikon part (as now verified by Chipworks). Now what does that mean? A lot and not much. I'll use a different product to illustrate my point: the Apple iPad.
At the heart of an iPad is something labelled the Apple A4. This is a chip manufactured for Apple by Samsung, using technologies licensed by Apple from ARM. Over the years, Apple combined its own internal processor R&D with several small processor performance tweaking companies, and that group is responsible for the actual layout of the A4 chip. But Apple didn't design the CPU cores nor they actually manufacture chips. So, what is that chip? A Samsung? An ARM? Or an Apple?
Obviously, an Apple with licensed technologies (ARM), and which is produced by yet another company (Samsung). In the case of the D3200, I suspect much of the same thing is afoot. The sensor does not seem to be fabbed by Sony. It tests very similarly to the Sony, so there's likely some licensed technology that are in both, or Nikon has come up with an alternative that tests the same as the Sony.
There's a key advantage to being close to the low levels of a sensor like this: if you control both the hardware and the software you can tweak performance in interesting ways. That's why Apple has an A4 and doesn't license one of the many existing variations of ARM that are around. And I suspect that Nikon is using the same strategy, as well. The software side in this case is EXPEED3 (which has some licensed technology in it, too). That imaging ASIC is becoming more important to the sensor design as we drive up pixel counts and need higher internal bandwidth in the digital parts of our cameras.
The D4 and D800, for example, are driving nearly 120MBps on the HDMI port, which means that the sensor and EXPEED3 processor need to be capable of keeping up. You want to be involved with the low level aspects of sensors, otherwise you're a slave to what one sensor designer thinks the world needs and you might not be able to do things like that clean HDMI output.
So, do I really care whether the D3200's sensor is "made by" Nikon or Sony or Aptina or whoever? No. I do care that the sensor has been picked, and probably tuned, to the design needs of the camera, though. To that end, Nikon seems to be doing a fine job lately, regardless of whose name is etched on the substrate.