A new set of photographs (PDF Link) showing off the inside of the iPad W-Fi have been published by the FCC. The Wi-Fi iPad contains a 3.75V 24.8 Watt-Hour battery, twin antennas—one routed to the rear Apple logo, and one routed to the volume button area—and a comparatively small logic board. The vast majority of the interior space is taken up by the battery; notably, the unit also includes dual speakers, a detail mentioned briefly in some of the early reviews of the device.
Update: iFixit.com has discovered and posted two images of the iPad Wi-Fi + 3G internals from the FCC. The images show the black antenna housing on the top of the 3G model, which does not appear to have any noticeable slot for the microSIM card, as well as the GPS antenna, which is attached to the backside of the display assembly.