It's now official, these couple of years of work have made it into an official JCP specification. Bean Validation is also part of Java EE 7 which has been approved too a few of days ago. We have already discussed the features at great length here but to do a short summary: support for method and constructor validation (via CDI, JAX-RS etc) integration with CDI (Validator and ValidatorFactory injectable, ConstraintValidator instances being CDI beans and thus accept @Inject, etc) EL expressions...
