Let's be clear why Nikon put 24mp in the D3200

Just a guess:

-> Based on NRs rumor, there will be no D400 but the D600: FX with similar specifications to the D300S (or D7000), with enhanced movie and 16MP D4 sensor (for about $ 2,300); No more DX pro or semi-pro models.

-> End of this year will come the successor to the D7000, called 7100, 7200 or 8000. This will be a "prossumer", top of DX, with the same 24MP sensor from sony;

-> At some point there will be a top FX to replace D3X, maybe "D4X" with the D800 sensor.

It makes sense for me !