58 megapixels in a DSLR
More interest to me is the idea of scaling up the D3200 sensor to full-frame size, which would yield a 58-megapixel full-frame DSLR.
In search of proof of concept of what a 58-megapixel DSLR might offer, I have posted at full apertures series from f/4 - f/45 from the D3200, along with a simulation of what 36 megapixels downsampled from 58 megapixels might look like.
In other words, the analysis shows exactly what a 58-megapixel DSLR looks like (same pixel density as the D3200), as well as what it would look like downsampled to Nikon D800 resolution.
My conclusion is that a ~60 megapixel full-frame DSLR is not only quite practical and useful, but an inevitable trend to beyond 60 megapixels, in the sense of thinking of a sensor as a sampling device to be used to produce images of exceptional per-pixel quality at somewhat lower resolution than the native sensor resolution, e.g. 36 megapixels from 58 megapixels, or 50 megapixels from 100, etc.
The only question is who will get there first, Nikon or Canon?
See my Nikon gear page for availability status.