What Nikon DSLR is best?

Okay for a while I was considering buying a Panasonic Lumix g2 but now I'm thinking about a Nikon so which dslr Nikon is the best?

Added (1). I'm a beginner with an interest in photography.

Nikon D5000

No such thing as an all-around-best-of-anything, it depends on your shooting style, level of expertise and the depth of your pockets! If I were buying a new Nikon this year I would get a D7000 but that's just me, it is more compatible with older "legacy" Nikkor lenses, and I won a number of legacy Nikkors.

The best is the Nikon d3x. It costs several thousand dollars.

If you are a photographer in photo studio, Nikon D3x is most recommended
If you are professional photographer for nature scenery, Nikon D3 or D3x
If you work for a sports magazine, D3s
If you are an amateur photographer but with great passion and money, D700 or wait for D700s
If you are a beginner, and has plan to update your camera, D3100 or D5100
If you are a beginner, and has plan to update your camera, and with extra money, D7000

Nikon D3100

If you have the budget, then there's no need to start at the bottom of the rung, you should skip the entry level step and go straight to advanced level cameras, the learning curve is more or less the same. The camera bodies you should look at are the D90 and the D7000.

I think Nikon's 18-105mm lens serves 90% of your needs quite well, buy that for now, and learn how to use it. Once you understands the basics in photography you can start deciding which lenses you really need.