The D60 is the third incarnation of Nikons compact, user-friendly entry-level SLR line that started back in 2006 with the D40(which replaced the first Nikonstarter model, the D50). The original D40 was a hugely important camera for Nikon and can be given a lot of the credit for the resurgence in Nikons fortunes at the volume end of the SLR market(which had been totally dominated by Canon since the launch of the EOS 300D / Digital Rebel).
The D40s success(which continued long after the D40X made its swift appearance only 6 months later) isnt hard to explain; it was keenly priced, nicely designed and built and capable of excellent results. It was also a camera that proved cameras do not sell on megapixels alone(even at launch its 6MP resolution was far fromclass leading).
The D40X, which was positioned as a premium alternative to the D40 rather than its replacement, didnt mess around with the formula much at all; a new sensor with more(ten) megapixels and a lower base ISO, plus a slightly higher continuous shooting rate. The D60 is a direct replacement for the D40X(the D40 will stay around for a while as Nikons budget option), and once again its not a major upgrade; the sensor remains the same(though now has a dust reduction system) and the external design is almost identical.
Theres a few new features, including the same Expeed processingconcept seen in the D3 / D300, Active D-Lighting, an eye sensor(to control the screen display), and some tweaks to the interface, but perhaps the most significant change isnt to the camera at all; the move to an optically stabilized version of the kit lens