And even odder may be that the pricing for both sets of computers is the same.
During his, Apple CEO Steve Jobs unveiled the Intel-based iMacs, promising that they would be as much as two to three times faster than their predecessors.
Apple could not immediately respond to questions about why it's continuing to sell computers that are now obsolete for the same price as their replacements.
According to one Jupiter Research analyst, Michael Gartenberg, there could be some continued demand for the older desktop machines from people who already have a large supply of older applications and aren't looking to upgrade immediately.
But Jobs said Apple's new Rosetta software will allow anyone running one of the new Intel-based machines to use their pre-existing applications. And Gartenberg added that the continued availability of both machines was more likely a tip of the hat to clearing off warehouse shelves.
"There is inventory, and when you have inventory, you sell it," Gartenberg said.
Meanwhile, Apple's new laptops, the so-called MacBook Pros, will also be priced in the same range as the old PowerBooks, even though Jobs said the new laptops will be as much as five times as fast.
The 15-inch PowerBook G4 with a 1.67GHz PowerPC processor currently goes for $1,999, while the new 15-inch MacBook Pro with a 1.67GHz Intel dual-core processor will sell for the same price. A souped-up 1.83GHz MacBook Pro will run at $2,499, the same price as the current PowerBook G4 17-inch machine with a 1.67GHz processor.
However, the new MacBook Pros, which Apple began taking orders for Tuesday, will not be available until next month, Jobs said.