Craft CMS version 4 is in development and rough release dates are available.
In the State of Craft talk at the 2021 Dot All conference, Pixel & Tonic CEO Brandon Kelly announced the following about Craft CMS version 4:
As of Craft 4, Pixel & Tonic is changing their release cycle to be yearly. Major releases will happen once per year and may include breaking changes. Point releases in between major releases should no longer have breaking changes.
As an example:
This new release cycle will help both plugin developers and companies developing with Craft plan their projects, updates, and release cycles against a more predictable Craft release cycle.