As they always do with any bit of new Apple tech, iFixit has posted a full teardown of the iPad on their site. Some things of note from their teardown:
-- iFixit broke some of the plastic tabs when pulling the display assembly away from the back case, so if you're looking into DIY repair of the iPad, keep that in mind.
-- The display assembly and rear case both weigh 350 grams each, meaning weight distribution front-to-back is exactly 50/50.
-- There is a large void in the upper right corner of the WiFi-only iPad. This is where the 3G chipset will live in the 3G-enabled iPads.
-- The battery (actually two batteries hooked in parallel) takes up most of the iPad's internal volume. It's a 3.75 Volt, 24.8 Watt-hour battery; by comparison, the iPhone 3GS has a 4.51 Watt-hour battery, while the MacBook Air's battery is 40 Watt-hours. The battery weighs 148 grams -- 13 grams more than the entire iPhone 3GS.
-- The display data cable connector is the same style as that used on Unibody MacBooks
-- The logic board itself takes up very little of the iPad's volume. Based on iFixit's screenshots, the entire logic board seems only slightly larger than the average adult's palm.
-- The iPad has 512 MB of RAM.
-- The Broadcom WiFi 802.11n + Bluetooth chip appears to be significantly larger than the chipset used in the iPhone. This possibly explains the lengthened bottom portion from the leaked photos of what's supposedly the next-gen iPhone's display.
-- The WiFi antenna, located behind the Apple logo on the rear case, is either similar or identical to the antenna used in the iMac.
-- That compartment on top that everyone thought would be perfect for an iSight? It turns out that compartment houses the iPad's ambient light sensor. iFixit suspects the compartment was intended for the light sensor all along, and that rumors of a camera were "overzealous."
Overall, the iPad's interior, much like the device itself, seems halfway between an iPod touch and a MacBook, drawing design influences from both ends of Apple's portable line. The iPad has an extremely tiny logic board given the size of the device itself, which is reminiscent of the iPod touch and iPhone's construction. However, the iPad's interior is nowhere near as cramped as either of those devices, with rather large void spaces that you'd be more likely to find in a MacBook. While the interior layout is very simplistic and clean, as we've come to expect of Apple's products, the iPad doesn't look at all like something the average person will want to take apart and fix.