In a surprise move, Apple updated the iMac at its big event today, showing some love to an iconic desktop computer that has long been eclipsed by its smaller more portable cousins.

In true Apple fashion, the latest iMac maintains its desk lamp design but has become dramatically thinner and lighter than its predecessor. It's just 5 mm thick at the edges, 83 percent thinner than the previous generation, and expands gently in back to house all of the computer's tightly packed components. The display itself is thinner and is now fused directly to the glass, just like Apple did with the iPhone 5. All-in-all the body of the new iMac is an incredible 8 lbs lighter than the previous model.

Inside, the iMac is still the powerhouse that you'd expect from a desktop machine. Like all of Apple's other recent computers, it has jettisoned the optical drive and added flash storage. A new development with the iMac, though, is something Apple calls "Fusion Drive," which actually retains traditional hard drive storage and uses it in conjunction with the flash storage. The Fusion Drive option is available in either 1 TB or 3 TB.

Performance wise, iMac comes equipped quad-core Intel i5 or i7 processors capable of up to 3.2 Ghz. And its got a dedicated Nvidia GeForce Kepler graphics chip set.

The new iMac comes in two sizes: 21.5 inches and 27 inches. The 21.5 inch model starts at $1299 and begins shipping in November. The 27 inch model begins at $1799 and ships in December.