There are a series of rumors suggesting that Apple will refresh the iPad with a 2nd generation model next March. Sounds like a reasonable rumor. I'd guess that the 2nd generation iPad will include cameras (both on the front and the back so that you can participate in Face Time), a retina display, and maybe it will have a widescreen display resolution. Would you prefer to see a narrower iPad? Maybe the next iPad will come with a built-in stylus pen so that you can draw pictures or jot notes on your iPad.
If Apple changed the physical dimensions of the iPad, then what would we do with all those 3rd party accessories?