Apple's yearly developer conference should see iOS 8, OS X 10.10, and likely some hardware.
Physical Mockup of Next-Generation iPad Appears at CES
Comparison of current iPad (top) and mockup of claimed next-generation iPad (bottom)
As noted by Engadget, however, one case manufacturer exhibiting its wares at CES has taken things one step further in aiding our visualization of the next-generation iPad by putting together a physical mockup of the device made out of machined aluminum.
It [the case] was so intriguing that we asked to put our own iPad inside, which is when we were told it wouldn't fit, since the case was designed for the next iPad. Indeed, the mockup that we found inside the case was a tad bit slimmer than the first-gen iPad, with a taper leading to the edges that reminds us of the iPod touch, and a home button positioned nearer the bottom edge. We found all the typical cutouts on the case, and their mirror on the machined mockup, including a large square for the speaker.The rumored physical details of the next-generation iPad of course depend on the case mockups being based on accurate information, although such details have generally been fairly accurate in the past as the case manufacturers have been able to obtain advance design information through leaks in Apple's supply chain. A number of the claimed cases have been pulled since their existence was made public, possibly suggesting that Apple has been stepping in to limit access to accurate details of its future products.
Aluminum mockup of claimed next-generation iPad (rear view)