Garnet OS
Garnet OS is the new name for the Palm OS. ACCESS Systems Americas (the new name of PalmSource) announced the new name with little more than a press release in January 2007 fufulling its obligation to discontinue use of the Palm trademark.
PalmSource?
In January 2002, Palm, Inc. set up a wholely owned subsidiary to develop and license Palm OS, which was named PalmSource. PalmSource's main business was to develop and license the Palm OS operating system. In October 2003, PalmSource was spun off as an independent company, and Palm renamed itself palmOne and acquired Handspring.
In late 2006, PalmSource was aquired by ACCESS, which specializes in mobile and embedded web browser technologies, for US$324 million. PalmSource later announced that it would rename itself to ACCESS Systems Americas.
Why the change to Garnet OS
As part of the spinoff on 2003, palmOne and PalmSource set up a holding company that owned the Palm trademark. In 2005 PalmSource sold its share in the Palm trademark holding company back to palmOne Inc for $30 million dollars. palmOne was then free to call itself Palm Inc, and PalmSource pledged to transition away from using the Palm name and trademarks.
January 25, 2007 - ACCESS announced the renaming of Palm OS to Garnet OS.
...But what about Palm OS
Palm OS was originally released in 1996 and the name has been in use for over 10 years to describe devices that run the Palm OS. It was originally developed by Jeff Hawkins for use on the original Pilot PDA by US Robotics. Version 1.0 was present on the original Pilot 1000 and 5000 and version 2.0 was introduced with the PalmPilot Personal and Professional. The Treo 680 and 700p today run the Palm OS Garnet v5.4. Today there are over 20,000 Palm Software applications for Palm OS.
To make matter even more confusing, in late in 2006 Palm Inc licensed the Palm OS Garnet Source Code from PalmSource. The agreement also provides Palm flexibility to use Palm OS Garnet in whole or in part in any Palm product, and together with any other system technologies. Palm plans to ensure that applications now compatible with Palm OS Garnet will operate with little or no modification in future Palm products that employ Palm OS Garnet as the company evolves it over time to support Palm's product differentiation strategy.
In other words, it's possible that Palm could make a device that continues to use the Palm OS that even uses a new operating system and they also could even still call it the Palm OS since they own the trademark and would still be actively developing what was left of Garnet.