Expression Language

In its most basic sense, making JavaFX an expression language means removing the distinction between statements and expressions -- statements (including blocks) have value (which may be void).
This simplifies the language, allowing, for example, one kind of if-statement, one kind of function definition, and allowing blocks within an expression without requiring anonymous functions.
The more controversial aspects of expression languages involve confusing syntactic constructs -- which can be grammatically disallowed.
The consensus was to make JavaFX an expression language, but not at the expense of clarity.