Think Secret, a Mac rumor Web site has gotten the skinny on what is allegedly Apple's re-designed iMac. The self-appointed sleuths breached Apple's culture of secrecy and posted an article detailing the specifications for 17- and 20-inch iMac G5s. The iMacs are rumored to be available in two 1.6GHz and two 1.8 GHz varieties.

According to the report, Apple is continuing to house components in an all-in-one casing that is mounted directly to the back of a flat display panel. Every model is equipped with optical digital output, a built-in microphone and enclosure mounted speakers.

In addition, the Macs are said to be AirPort Extreme ready and upgradeable to 2GB of DDR RAM; although, they may lagging behind their Intel counterparts and be equipped with marginally competitive amounts of memory.

As always, sources close to Apple are promising that the iMac will be "an eye catcher," similar in appearance to Sony's VAIO W700G.

Apple CFO Peter Oppenheimer confirmed the company's intention to launch new iMacs in September. Apple claims that production problems stemming from problems at IBM's chip fabrication facilities will be settled in time for the launch. IBM recently switched to a 90-nanometer scale process.

The most basic new iMac model will be geared toward the education market and may feature a 17-inch widescreen display. Think Secret posted more detailed specs for the iMac which listed, "a 40GB Ultra ATA hard drive; 256MB of DDR SDRAM; a 512K L2 cache; an NVIDIA GeForce4 MX GPU with 32MB of DDR video memory; VGA video output, S-video and composite video output; 10/100BASE-T Ethernet, two FireWire 400 ports, three USB 2.0 ports, and two USB 1.1 ports on the keyboard."

Another entry level model may share the same specs except for the addition of "a slot-loading Combo drive, 80GB Serial ATA hard drive, NVIDIA GeForce FX 5200 Ultra graphics processor with 64MB of DDR video memory, and a 56K internal modem."

Think Secret also reports that 20-inch widescreen iMac may come equipped with the same features as the base model but could pack a more potent punch with a 1.8GHz G5 processor, NVIDIA GeForce FX 5200 Ultra graphics processor with 64MB of DDR video memory, slot-loading SuperDrive, 80GB Serial ATA hard drive, and 256MB of DDR SDRAM. The top-of-the line model may be identical except for having larger storage capacity at 160 GB.

Pricing is expected to be in line with current iMac models - in the $1,300 to $2,200 USD range – and models will begin to hit the shelves in September.

Apple intends to formally announce the iMacs during a keynote address at the August 31st Apple Expo. The keynote will be delivered by Apple Vice President Phil Schiller. Apple CEO Steve Jobs, the customary master of ceremonies, has been battling Pancreas cancer.