Shenzhen MacTop Electronics has posted (English translation) a picture of what is supposedly a case for the next-generation iPad, complete with more pronounced curvature and a hole for a rear-facing camera. Also, the speaker slot (assuming that's what it is) is much larger than what's currently on the iPad. The tiny hole that we assume is for a camera is in the upper left-hand corner, similar to where the camera lives on the iPhone and iPod touch.
As MacStories notes, it might be odd to shoot photos with that gigantic thing, but what do I know? We'll find out soon enough, as the so-called "iPad 2" is rumored to hit shelves in April of next year.