SmartXX, creator of Xbox mod chips, have somehow gotten their hands on three Xbox development kits and are almost certainly reverse-engineering the new console as we speak. There’s no explaination of how a group of mod-chippers got access to three dev kits months before the retail versions ship, but they did post a 40MB zip file full of high-resolution pictures. The zip files contains pictures of various parts of the motherboard, dvd-rom, HD cables, memory cards, headset, strange power connector and massive power adapter.
You can read about SmartXX’s developments on their website, or on their forums. Xbox-scene has mirrored the pictures "just in case."