The pictures were taken with a Canon Powershot A480. Same distance, same zoom setting on the camera for each device, and the same lighting as much as was practical (one room light and a spotlight directly on the screens from about 4 inches off to one side, except for the iPad of course which gives off enough light on its own to flood a room...)
You haven't got a free zoom on the jetBook, you can only pick 50%, 75%, 80% etc. so I cropped the document using Briss to about what was showing on the other two devices.
You're right in that what the camera picks up isn't necessarily how your eyes see things. The jetBook screen is quite muddy (low contrast and dark) in comparison to the Sony PRS-T1 unless you have lots of light flooding on it (like I do in these shots). I expect it will look fantastic in full sunlight, but in a dim room at night it's a bit disappointing.