Grails 1.4 should actually come after Grails 1.3.
SpringSource recently decided to cancel 1.4 and name the next release 2.0.
A lot of improvements and new features justify the new major version number.
The changes of the upcoming 2.0 release include:
- New console UI and interactive mode
- Enhanced error reporting and stack trace printing
- Improved development time reloading with a JVM agent
- Performance enhancements
- AST transformation API for plugin devs
- HTML5 scaffolding
- Static resource handling
- A formalized GORM API
- Abstract inheritance support
- Multiple data sources support with 2 phase commit
- Database migrations and reverse engineering
- Upgrades to libraries from Groovy 1.8, Spring 3.1, Hibernate 3.6 and Servlet 3.0
- Completely new Testing API with Spock support
- Unit test scaffolding and enhanced unit test output in the console
Grails 2.0 is scheduled for september 2011.
See the Grails mailing list for more details.