In his speech “State of the Word” Matt Mullenweg, co-founder of WordPress and founder of Automattic, made a huge announcement by saying that there will be no major release in 2017. This means we will not see a WordPress 4.8 next year. Naturally there will be minor releases, updates and bug fixes.
This announcement should not be seen as a sign of stagnation – quite the opposite. Future development should focus on performance and fixes tot he REST API, the editor and the Customizer. New major versions of WordPress will not be released until these features are ready.
Shifting from a time-based release cycle to a project-based one really is a pretty surprising announcement.