Just a few days after the orginal post with Solaris 11.x plans, Oracle just provided an update on the official Solaris blog.
Starting with Solaris 11, OS development and update will follow a continuous delivery model, whih means the next few years will see lots of incremental improvements within 11.x instead of a major release like Solaris 12.
It’s also very good to see that extended support is planned for the next 25 years or so:
As we will deliver new features and capabilities as part of Oracle Solaris 11, we have extended the Oracle Solaris 11 and Oracle Solaris Cluster 4 Premier and Extended Support lifespans to January 2031 and January 2034, respectively. Support dates are evaluated for update annually, and will be provided through at least the dates above.