The D7200 release date and shipping starts in April and the body only will cost around $1,199.95 as you can find out on the D7200 product page. That means the D7200 will cost around $200 more than the D7100, however, you probably can expect that the price of the D7100 will decrease a little bit in April when the D7200 is shipping.
The D7200 comes with built-in WiFi and NFC, that means you don’t have to buy an adapter as you would need with the D7100. However, many people wished the D7200 would also feature an articulating screen, but as the D7100, the D7200 won’t have a tilt screen either and that is pretty disappointing for many. If you want to see a full comparison of both cameras, check out the Nikon D7200 and D7100 comparison sheet.
Here are some major changes: Nikon did increase the buffer for the D7200 significantly while the camera can shoot 6 FPS in continuous shooting mode. The increased buffer will support up to 100 JPEG photos and up to 18 shots of 14-bit RAW files. If you set the quality to 12-bit, the buffer will be able to hold around 27 shots. They also increased the battery life from 950 shots to around 1110 shots. Apart from that the camera will feature a higher native ISO range (ISO 100-25,600), the camera has an upgraded AF system (sensitive to -3EV vs. -2EV) and the camera will use the EXPEED 4 Image Processor. All the other changes you can find in the comparison sheet are rather minor.
You can already find several people complaining on social media sites and in photography related forums that the D7200 is just a micro upgrade to the D7100. Others expect that this camera will do far better in burst mode and low-light scenarios. I think we need to wait, to find out how well the D7200 is doing, we might find first samples and reviews very soon.