Some of the key features include:
- 16.2 Megapixel CMOS sensor. Similar to the D7000 sensor the D5100 allows you to print even bigger prints with maximum resolution.
- Vari-angle LCD. Nikon finally fixed the movable LCD that first debuted on the D5000. Upgrading it to a hi-res 920K dot and moving the swivel to the left side. This will be a great improvement for those who are shooting a lot of videos and want to be able to see what they're filming when shooting from odd angles.
- 1080p Video. This was a no-brainer. True 1080p HD video is a requirement on all DSLR's these days. It's too bad that they didn't realize this in the beginning.
- 14bit RAW. This is something that was previously only available in the high-end Nikon cameras such as the D300s and the D700. 14bit processing expands the dynamic range of the images and should allow for less noise at high ISO's and better control of shadow/highlight detail.
I would have liked to have seen the number of focus points increased. The D7000 has 39 points and I was hoping that the D5100 would get an upgrade to 19 or 21 points for more accurate focusing.
All in all, this is a pretty nice camera and like the D7000 I think Nikon has a real winner on their hands. This camera should be flying off the shelves once it's commercially available.