new 21.5in and 27in iMacs
For iMac fans the world over, the long wait is over: Apple has at last announced a refreshed iMac.
The update is long overdue in many users' eyes, as the previous version was launched in May 2011, almost prehistoric in computing terms.
The new iMac doesn't get a Retina display, but while that will disappoint some, others will be glad they waited.
Not only is the new model impossibly thin, with edges just 5mm thick, but it also has the latest generation of Intel's Core i5 and i7 processors, USB 3, the option of SSD storage or a combination of SSD and hard drive, which Apple is calling Fusion Drive.
New 2012 iMac: screen
There are two iMacs, with exactly the same screen sizes as before: 21.5in and 27in. They keep the same resolutions, too: 1920 x 1080 and 2560 x 1440 pixels respectively.
The new, thinner LCD in-plane switching (IPS) screens are now laminated to the front glass, just as in the iPhone and iPad, which saves space (there was a 2mm gap on the 2011 model) and also makes everything look brighter and clearer.
Importantly for designers, the new screens are 75% less reflective than the old iMac, which was like a mirror. The screens are individually calibrated in the factory, too.
New 2012 iMac: design
The new iMac retains the design of the outgoing 2011 model, replete with aluminium 'chin'. However, rather than laser welding the chin to the aluminium rear panel, Apple now uses a technique called friction stir welding. This is where the molecules of the two pieces are "merged together" to make one super-strong, seamless part.
Of course, the back edges are tapered to provide more room for components in the middle of the iMac.
New 2012 iMac: specifications and ports
Apart from the thinness, the new iMac looks much the same at the old version - that is to say one of the best-looking all-in-one computers around.
Inside the aluminium shell, of course, things are very different. The optical drive has gone, but "for those who want to remain stuck in the past" as Phil Schiller put it during the launch event, you can attach an external Super Drive.
There are quad-core Ivy Bridge Core i5 and i7 processors, up to 3TB of hard disk space, nVidia graphics, up to 32GB of RAM (twice as much as before) and up to 768GB of SSD storage. There's also 802.11n Wi-Fi and Bluetooth 4.0.
As before, all the ports are tucked out of sight on the rear panel, making it tricky to insert an SD card or USB flash drive. There are four USB 3 ports, two Thunderbolt connectors, gigabit Ethernet and a 3.5mm headphone output.
New 2012 iMac: Fusion Drive
If you don't want to be forced to choose between a hard drive and SSD storage, you can opt for a so-called Fusion Drive. This combines a 128GB SSD with a 1TB or 3TB hard disk.
This appears to the operating system (Mountain Lion) as a single volume, but the OS and all the pre-installed apps are stored in flash memory for the best performance.
Your documents and apps are stored on the hard disk but OS X works out what you use the most and automatically stores those apps and documents on the SSD for better performance. If space runs low, it will swap less frequently used apps onto the hard disk.
New 2012 iMac: price
The new iMac starts at £1099 for the 21.5-inch model. This has a 2.7GHz quad-core Intel Core i5 with Turbo Boost speeds up to 3.2 GHz and an nVidia GeForce GT 640M graphics chip
If you want a 2.9GHz quad-core Intel Core i5 (Turbo to 3.6GHz) and an nVidia GeForce GT 650M, you'll pay £1249 inc VAT.
The 27-inch iMac costs from £1499 with a 2.9GHz quad-core Core i5 and an nVidia GeForce GTX 660M. For £1699 you get a 3.2GHz Core i5 and an nVidia GeForce GTX 675MX.
All models come as standard with 8GB of RAM and a 1TB hard disk.
New 2012 iMac: launch date
The 21.5-inch iMac will be available in November through Apple's website, retail stores and Apple Authorised Resellers. The 27-inch iMac will be available in December.