Apple Insider spotted two new model numbers within the lines of code for Mountain Lion's dual-booting Boot Camp assistant software.
This included the 'MP60', thought to be the next Mac Pro tower, and the 'IM130', potentially a new iMac.
At the WWDC 2012 event, Apple announced a major revamp to its MacBook range of laptops, including various upgrades such as faster Intel chips and a model with a Retina Display.
Apple also rolled out a relatively modest update to the current Mac Pro line, leading some to suggest that the firm intended to phase out the desktop range in favour of more lucrative laptops and mobile devices.
But asked about plans for its desktop range by a concerned customer in June, Apple chief executive Tim Cook said that the firm was "working on something really great for later next year".
Apple has a packed end of year in terms of new products, with the new iPhone and potentially the iPad Mini small-screen tablet rumoured for launch.
The firm may therefore look to launch a new iMac and Mac Pro in 2013. It is thought that the models will not feature optical drives.
Apple Insider feels that Apple will opt to incorporate high-performance SSD RAID options in its new desktops as a way to create "a reduced profile" for the products.
Other speculation has suggested that the range will come with monitors featuring the Retina Display that is now on the newer iPhone, iPad and MacBook Pro.
Apple has been selling more MacBook laptops than desktops since 2006, but it remains a strong player in the desktop space, particularly with the ongoing woes for PC manufacturers.
Mac users can download Mountain Lion now from this link.
> Apple's OS X Mountain Lion roars past 3m downloads