Oracle published a new roadmap and Solaris 12 is absent. A new blueprint dated January 13, 2017 expunges any mention Solaris 12 in the places where Oracle had included it in the 2014 edition. There is a mention of “Solaris 11.next” as due to debut during this year or the next complete with “Cloud Deployment & Integration Enhancements”.
You can’t find any mention of “Solaris 11.next” anywhere on the worldwide wibble.
Oracle does mention SPARC Next appearing this year in 2020 SPARC Next+. It also hints of plans to launch SPARC infrastructure-as-a-service, probably under the brand “@Customer” with services in “Dedicated Metered & Non-Metered” form.
It appears that there will not be a full new version of SPARC but the existing flavour will be enhanced and will be supported for many years to come.
While it is not the end of Solaris which some have predicted, it does seem to indicate that Oracle has not much will to push through a full version.