I am curious as to how many people are having the same issue with the display hinge being looser than expected. My fathers machine seems to have a much tighter hinge than mine. We performed the following test, and I am curious as to how many others are "failing" this test. I went to the Apple store to check out their machines and the test went 60-40 in favor of passing the test.
The test was performed as follows:
1. Put the display at a 90 degree angle perpendicular to the keyboard (the straight up position)
2. Turn the machine so the back of the display is parallel with the floor and the keyboard is perpendicular to the floor.
3. Even out the display again so that it is exactly parallel with the floor.
4. If the display moves towards the fully open position, while only under the force of gravity, it failed the test.

I am happy with my machine besides the hinge issue. I am just nervous about returning it and having the same problem again. Is anyone else experiencing this?