Pre-orders for the device and its 9.7" multi-touch display will kick off in Apple Retail Stores and the Apple Online Store next Friday, March 16.

In all, a total of six iPad models are due across April. As planned, the Wi-Fi models--16GB ($499), 32GB ($599), 64GB ($699)--will be the first to launch when they hit April 3.

Models supporting both Wi-Fi and 3G data transfer--16GB 3G ($629), 32GB 3G ($729), 65GB 3G ($829)--will then follow in late April, with AT&T offering two contract-less 3G data plans in the United States: 250MB at $14.99 a month or unlimited at $29.99.

All versions of the iPad will be compatible with the downloadable iPhone games and software available through the iTunes App Store--the iPad can display these programs in windows mode (original resolution) or full-screen (via pixel-doubling)--though various developers are already readying iPad-only Apps to take advantage of the hardware.