If you do not have a $1,500 but have $1000 for a Nikon DSLR camera, then get the Nikon D90. The Nikon D90 price is currently $1,000 - $1,300 in Amazon. I think now is the right time to buy Nikon D90.
Nikon D40 and Nikon D60
If you want to improve your shooting skills, get a Nikon D90 instead of the Nikon D60 and Nikon D80. This DSLR camera has many cool extra features. For example, it features a depth-of-field preview button.
Another great reason to get a D90 is that it produces nice photos in nearly all picture-taking situations. This is afforded by its Auto ADR feature, which is always on by default.
What about the Nikon D80?
The D80 is more expensive, but that does not translate to quality and performance. While it costs less, the Nikon D90 is an excellent upgrade. Here are some Nikon D90improvements that I like: 1-stop extra ISO up to 6400, option to go for a VR 18-105mm kit lens, 2 extra MP, and 3-in LCD screen with higher resolution.
What about the Nikon D300 and D700?
The Nikon D700 and Nikon D300 are much tougher babies than the Nikon D90. They are also much faster if you shoot a lot of sports. But the Nikon D90 performs just as well as the Nikon D30 and Nikon D700 in terms of image quality in good light.
Paying more for a Nikon D300, Nikon D700, or Nikon D3 will give you faster frame rates and focus and better durability, but that is it. On the other hand, the Nikon D90 provides these advantages while having terrific image quality and great LCD screen.
Other nice features
The D90 has many selling points that give you value for your money. One features that I really like about this DSLR camera is that it can record HD movies. The Nikon D90 has an ergonomic handling, and it eliminates the flawed exposure metering of the Nikon D80 and Nikon D40; the flash metering is also perfect.