The special media event of Apple, slated on Oct. 16, is expected to bring in announcements on the much-awaited 27-inch iMac that is said to have the Retina quality display.

Apple said that the product is ready for shipping before the end of 2014. However, the product's 21-inch model, which is currently on a development phase, is said to be released in the beginning of 2015. The 2015 offerings may include other notable products such as Photos for Mac and Apple Watch.

Apart from the iMac, Apple is also gearing up to reveal the next generation of iPad Air. According to Ming-Chi Kuo, an analyst from KGI, shipments of iPad Air 2 may be constrained. 

"Of the new products, we think the market will be more interested in iPad Air 2," says Apple. "However, as the poor yield rate of anti-reflective coating cover lens has delayed mass production, we estimate 2014 shipments of iPad Air 2 of seven to nine million units, lower than the 12 million units of the then-new iPad Air shipments in 2013."

The number is in sharp contrast to the release of the original model of iPad Air, which amounted to 12 million units. The iPad mini is also not getting any updates at this time. Perhaps to compensate for that is the news that the company is working on a 12.9-inch iPad, although there's no word yet on when it will be released. 

Kuo explains that the delay in the shipments of the two iMac models with the Retina Display, the 27-inch and 21-inch versions, is based on the fact that there is difficulty in developing two high-resolution panels of varying sizes in the same period.

Apple's MacBook line is unlikely to get any major upgrades this year. KGI attributes it to shipping delays at Intel, which have compromised the availability of the latest processors. This means that a 12-inch MacBook Air or the next generation of MacBook Pros may just launch sometime in 2015.

Apple's press event is on Oct. 16, 10am at the Cupertino headquarters. It is also speculated that Apple is announcing the launch date of its OS X Yosemite, the next-generation Mac operating system. It features enhanced interaction with iOS devices by way of new Continuity options. Other products rumored to be announced at the event include Apple Pay and iOS 8.1.