I've had mine for three days. I've barely used it. It's a black 60 GB. So far, no scratches that I can see, but what looks like one dead pixel (I've lived with one on my iBook for 4 years, I can live with one on my iPod), and the thing picks up finger prints and dust everywhere. The finger prints obviously are there on the old ones, too, one just didn't notice them as much because of the color and the different material (the face of the 3G at least IS different, not the same clear plastic as is on face of the 5G).
By comparison, it was months before there were any noticeable issues with my 3G (which I'm still using as my primary iPod until they come out with some dockable accessories), and that was a key scratch due to my own negligence.
My guess is that the clear facing material (which used to be limited to the LCD, but now covers the front of the iPod), the black color, and the fact that it is a video device (which makes the quality of the screen much more important), will lead to more noticeable scratches, just as the material, the black color, and the pocketability lead to more noticeable scratches on the Nano.
By the way, I think they should have rotated the iPod 90 degrees, giving them room for a larger LCD, and put in a smaller (nano-sized) click wheel on the right hand side (but made the video screen reversible and the fast-forward/rewind controls switchable, so one could put the click wheel on the left, though how they would have managed the play icon in that circumstance I don't know). Then again, I don't know how ergonomic that would be with the click wheel, though I think holding an iPod landscape would be more ergonomic for watching video.