Preview at WWDC likely in June, followed by September launch.
Next-Generation iMac With SD Slot, Quad-Core, Possible Xeon? New Mouse and Remote in Pipeline?
While details of the update have been scarce, Mac4Ever's sources point to the inclusion of an SD card reader, as found in the 13" and 15" MacBook Pro, and the use of quad-core processors, which conflicts with a subsequent report claiming that the new iMac will continue to use dual-core processors. Interestingly, one of the sources also spoke of the inclusion of Xeon processors, which would presumably only be used in high-end configurations if the information proves accurate.
Mac4Ever's sources have also reported a number of other tidbits about Apple's product pipeline for the next few months, including a new 100% touch-enabled mouse capable of advanced mouse functions, as well as a new aluminum Apple Remote. Other claims include a continued shift of Apple's software to 64-bit and optimization for Snow Leopard, as well as the much-rumored tablet, which sources vaguely claim will be very different from concepts that have appeared on rumor sites thus far.