Arstechnica: Apple isn't normally the first company to put new chips from Intel, AMD, and Nvidia in its products, but the wait for the new iMacs has been long by any standard. Some 19 months have passed between the early May introduction of the 2011 iMac and the late November shipping dates for this year's models. But the Intel CPUs and Nvidia GPUs the 21.5-inch model uses were both available months ago, and these desktops haven't made the jump to a pixel-quadrupled "Retina" display.
Visiting Apple's website reveals that the 27" iMac shipping times are between late June and early July. The 21.5" iMac seems to be in stock, however. The 27" iMac is backordered on Amazon as well.
The Macintosh or Mac is undoubtedly the most iconic computer there is. Apple has been at the forefront of design and build quality when it comes to its computer products. Unfortunately, Apple is known to charge a steep premium on all of its Mac products, be it the MacBook, MacBook Pro, iMac, Mac Pro, and the Mac Mini. What is worse, while there is no doubt at all that these products are made well, they are not the best in terms of performance. This is basically why there is a small niche in the market for Hackintosh machines that are basically a rough copy of a Mac.
Apple's smallest all-in-one features a great design and fantastic 4K display. Just make sure you upgrade to the Fusion Drive (at the very least) for faster boot and resume times.