Amazon description is up; looks like I was right on the external hard drive option:
Console Size – Approximately 1.8-inches tall, 6.8-inches wide and 10.5-inches long.
New Controller – The new controller incorporates a 6.2-inch, 16:9 touch screen and traditional button controls, including two analog circle pads. This combination removes the traditional barriers between games, players and the TV by creating a second window into the video game world. The rechargeable controller includes a power button, home button, +control pad, A/B/X/Y buttons, L/R buttons and ZL/ZR buttons. It includes a built-in accelerometer and gyroscope, rumble feature, camera, a microphone, stereo speakers, a sensor strip and a stylus.
Other Controls – Up to four Wii Remote (or Wii Remote Plus) controllers can be connected at once. The new console supports all Wii controllers and input devices, including the Nunchuk controller, Classic Controller, Classic Controller Pro and Wii Balance Board.
Media – A single self-loading media bay will play 12-centimeter proprietary high-density optical discs for the new console, as well as 12-centimeter Wii optical discs.
Video Output – Supports 1080p, 1080i, 720p, 480p and 480i. Compatible cables include HDMI, component, S-video and composite.
Audio Output – Uses AV Multi Out connector. Six-channel PCM linear output through HDMI.
Storage – The console will have internal flash memory, as well as the option to expand its memory using either an SD memory card or an external USB hard disk drive.
CPU – IBM Power-based multi-core microprocessor.
GPU – AMD Radeon-based High Definition GPU.
Other – Four USB 2.0 connector slots are included. The new console is backward compatible with Wii games and Wii accessories.