Bleeding-edge, Mainstream, Late-adotpters... it's a bell-curve.
The concept of early- to main- to late-adopters are developed for the
general purchasing behavior without product quality in mind. In addition,
other factors, such as purchasing power, macroeconomics conditions,
competition forces, etc., all will change the curve.
I am not saying or implying Vista is good or bad, just to clarify the thesis
of so-called consumer purchase behavior.