I just got my iPad today as well and am seeing the same thing. I first noticed it when I picked it up in portrait mode with my right hand (with the smart cover hanging off the left, adding a bit of weight). When I'm just holding it statically, the weight of the iPad doesn't make the distortion appear. But if I just adjust the iPad's position in my hand, the added dynamic force will make it show up.
Here's a pic of what I see. It's the 2 dark spots under the right side of the search box (the image is a bit blurry because I had to be moving to catch the distortion). As Andyw mentioned, no matter where I press, the distortion stays in that spot.
View attachment 508352
I was going to try and exchange it at an apple store (2 hour drive

) but now I'm concerned it might be a widespread "feature".
Edit:
Hmmm, I just realized that you guys were talking about it happening on a "dark" screen instead....