Digital photography

It's pretty much the same as 2010's D7000, with the addition of a stereo mic and headphone jack for video, a higher-resolution sensor, 51 vs. 39 AF points, a slightly larger LCD, and a first in any SLR: an OLED data display in the finder (Sony, Fuji and other cameras with OLED finders today aren't SLRs).

   The D7100's OLED display is just for the shooting  data in the finder, not the finder image display. From the 1980s through  yesterday, all electronic Nikon finder data displays have been LCDs,  usually backlit with a green LED. 
   There's also an inexplicably silly 1.3x crop mode, in which the frame rate climbs to 7 FPS. The 1.3x crop is inside the  [1.5x DX crop](http://www.kenrockwell.com/tech/crop-factor.htm) to make it a total of a 2x [crop factor](http://www.kenrockwell.com/tech/crop-factor.htm).
   In live view only, a new "spot" white balance mode. 
   The rear LCD adds auto brightness control. No  previous Nikon's auto LCD brightness control has worked properly; so  we'll see about the D7100. 
   The D7100 is very slightly bigger than the D7000, and very slightly (0.5 oz or 15g) lighter than the D7000. 
   There's a new *"i"* button for recalling recent settings, and just like the D600, there is now a lock button in the middle of the mode dial. 

   **Missing compared to the D7000 **
   Missing compared to the D7000 are the 640-pixel  resolution video modes. No analog A/V output cable is included, so the  D7100 may lack NTSC/PAL analog video outputs. 
   The finder only adjusts from as far as -2 diopters, from the D7000's -3 diopters. Both go to +1 diopters.  
   No LCD cover. 
   The D7100 has the same battery and charger as the  D7000, but is rated for 10% fewer shots per charge (only 950 for D7100  versus 1,050 for D7000). 

From Ken Rockwell's review of the D7100.