Apple's online store now lists a 10-day wait for all iMacs, except the low-end $899 model. Apple usually lists a one-day time frame for shipping its standard models.
The 10-day wait would postpone shipments until after Apple CEO Steve Jobs' July 18 keynote address at Macworld New York, a forum Jobs often uses to unveil new models. And such a time frame would give computer buyers the chance to change their orders based on any announcement Jobs makes.
"That certainly makes me think that we are going to see new consumer products at Macworld," Guernsey Research analyst Chris LeTocq said.
One reseller told CNET News.com that although Apple has not outlined what changes it will make to the iMac, it is pretty clear that something new is imminent. "I think the handwriting is clearly on the wall," the reseller said Monday.
A dwindling supply of products ahead of a Macworld trade show has often been a harbinger of which models will be updated.
Apple representatives declined to comment.
The company last updated the 3-year-old iMac line in February, adding the option of rewriteable CD drives and two psychedelic colors, the tie-dyed Flower Power and Blue Dalmatian, a light blue computer with white polka dots.
With last week's confirmation that Apple is discontinuing the PowerMac G4 Cube, speculation is running high that Jobs will introduce a flat-panel version of the iMac, at least at the high end of its consumer line.
However, LeTocq said Apple may need to keep the traditional iMacs around to hit the right prices for the low end of the consumer market and for schools.
"Eventually, even that will go away as (the price of) LCD panels comes down," LeTocq said, referring to liquid crystal displays used for flat-panel monitors and notebooks.
Changes may also be afoot for the Power Mac, Apple's professional line. All of the single-processor Power Macs show a 10-day wait for shipment at Apple's online store. The reseller noted there are still quite a few of the current Power Mac models in the distribution channel but said he expects upgraded models to be announced soon.
"I do anticipate there will be a change, at least a speed bump," the reseller said.