ThinkSecret reports that Apple is readying an iMac update and provides detailed specs from "reliable sources".
The new machines are said to be released with Mac OS X 10.27 and have 2 base models: 15" and 17" with processor speeds of 1GHz and 1.25GHz respectively. New models are reported to receive larger hard drives, graphics card updates, and USB 2.0. But no FW800
Last iMac upgrades were in Feb, 2003. Our Buyer's Guide notes that iMac updates are coming due.