A few weeks ago we were introduced to Nikon’s inadmissible new flagship, the D4. The $6000 DSLR camera has many ISO steps, a 16.2MP sensor, a new processing core, loads of professional features. If you are a Nikon photographer, who needs a camera that can do it all, the D4 is probably the best solution; but this camera is very expensive and many features you just might not need, like built in Ethernet connection. Amateurs prefer the D800 camera, it is cheaper.
The Nikon D800 is the replacement of the company’s $3000 D700 camera. As a consequence, the camera is similar to D4, with a reduced set of features and some significant adjustments, but not as much as the D700 was such the Nikon D3. The Nikon D800 is not a fully comparable camera and it will rest distant from the D4 in some crucial field.
The Nikon Nikkor DX VR 55-200 mm f/4-5.6G is an entry-level telephoto lens designed for use with DX format digital SLR’s like the Nikon D80. This lens is designed to compliment an existing general-purpose kit lens so if you have the 18 – 55mm kit lens this one takes over where the other one stops, extending your coverage to an equivalent of 300mm. That’s a pretty respectable telephoto performance and will allow you to get really close to your subject. 
Nikon have managed to produce a truly amazing camera in the Nikon D3100 and at a price that is somehow still affordable. It has many of the same features of pro cameras that cost many hundreds of dollars more. The closest competitor to the D3100 is the Canon EOS Rebel T2i but this camera seems to have the edge over it. It’s clear that Nikon put all their effort into making a camera that produces great images and didn’t worry too much about the specs or any wacky features that won’t add much value.