In particular, a person familiar with the matter says the Mac maker is informing some of its distributors not to expect any further stock of the entry level 21.5-inch, 3.06GHz iMac, implying that production of that model has ceased.
Meanwhile, those with ties to the company's stateside reseller channels are being advised to sell through their stock of all existing iMac models and to keep their inventories as lean as possible for the next few weeks.
These anomalies are similar to those reported by AppleInsider last month when it predicted the imminent the arrival of HDMI-equipped Mac minis, which turned up a few weeks later.
Apple has been plotting the upcoming iMac refresh since last year. At the time, the company was brainstorming a lineup that would include more than one quad-core configuration, according to people familiar with the plans.
Potential configurations included a dual-core Core i5 model, as well as quad-core Core i5 and Core i7 configurations. Also of interest, according to those same people, were indications that new iMacs would be the first Macs to employ Intel's Core i3 processor at the low-end, which would have the new family of desktops utilize all three flavors of Intel's mobile Core line of processors.
That said, it's not clear whether Apple has recently decided to alter any of these plans, especially in light of shortages (1, 2) of Intel's less brawny Core offerings. (Readers can see a list of Intel's Core lineup here.) Also unconfirmed is a recent report that the new iMacs would usher in USB 3.0 support and a faster FireWire interface.
The USB 3.0 specification, which was in Apple's hands over a year ago and targeted for a June 2010 release, is said to be be ten times faster than the current Hi-Speed USB standard (USB 2.0), and also more power-efficient, leading to lower active and idle power requirements. Like its predecessor, USB 3.0 is backward compatible with USB 2.0 devices.
Meanwhile, it's believed that Apple continues to work on the first Macs destined to adopt microprocessors from Intel rival AMD. It also holds a couple of Pro-related advances in its labs, namely a 12-core Xeon-based Mac Pro and a 27-inch LED Cinema Display, both of which appear to have slipped past their expected arrival dates.