Well, I think I understand your concern. I'm not sure that I see a
true imperfection, but it doesn't matter what I am seeing or feeling
in this particular body. Your concern over the body is interfering
with your enjoyment of the camera. I suspect you have similar
concerns about other material things that you own. Perhaps not to
this degree.
So, rather than beating you up or trying to convince you that others
could easily live with any minor problems, let's look at the
alternatives.
Here are a few thoughts:
1. As others have suggested, go to a local camera store and look at
both their display model for this body, and if they will allow you, a
new one out of the box. Some stores are more generous with their help
than others. You might take your camera with you and talk directly to
the manager, who will have more clout than the sales clerk. Sometimes
Ritz is easier to deal with than Circuit City or Best Buy if you are
in the U.S. And their displays are restrained from the hands of the
wandering public.
2. If you see similar imperfections, then decide if you want to stay
with Nikon. Remember, plastic bodies are not as rigid as metal ones
and there will be some degree of movement if you press on the parts.
Also, I suspect it is a bit more difficult to have perfect edge
alignment of the parts in anything such as this since it is mass
produced. No brand name camera builds bodies by hand unless you go
to, perhaps, Leica or Hasselblad and that's even doubtful.
3. If your body alone has the imperfection, see if your dealer will
make a goodwill exchange. If you are beyond the exchange period,
usually 10-14 days, then you may have to keep it.
4. At this point, you can keep it and try to see if the quality of
photos outweighs the disappointment in quality of construction. If it
does, then focus your attention on this. If not, you will need to
sell it to recoup some of your cost and try another brand.
5. Good luck. I hope you find satisfaction in some type of solution.