The following images are both the same frame, from Space Cowboys. Here we're comparing the VPL-VW90ES to the lower cost VPL-VWPro1 projector. As you compare, the shadow detail seems comparable. What is noteworthy, however, is the real advantage the VW90ES has in terms of blacks. The exposures are almost comparable (and intentionally overexposed, with the 90ES a touch more overepxposed than the Pro1 - look at the red light and other bright areas), yet, the blacks are blacker with this 90ES.
Our last comparison uses the night train scene from Casino Royale. Look to the trees and shrubs on the right, especially just above the tracks. The first image is the Sony VPL-90ES, followed by the same, but more overexposed. Next, the HW15, fourth is the Epson Home Cinema 8700UB, followed by the JVC RS15, and the last one is from the Runco LS-10d projector.
Shadow detail performance is really very good. No issue here at all. Plenty of details in the darkest areas of the woods, with the shrubs by the tracks and so on. Not the very best, but close enough. Remember, when setting brightness correctly, the difference between the two closest settings (one a tad too "bright" one too "dark") impacts the shadow detail. In the side by side above, for example the Epson slightly beat the Sony, but if I changed the Sony's brightness, by +1, it would no doubt match or beat the Epson slightly, but the black level would also raise. Again, these are small differences