Some specifications related to Java EE 7 already became Final. One example is the JavaServer Faces 2.2 (JSR 344). But you don't have to wait for the release of Java EE 7 and the final version of GlassFish 4.0, which is the reference implementation, to try all the new stuff. I've blogged about Maven and its integration with GlassFish Embedded in a way where you can, with just few steps, create a Java EE 7 and then run GlassFish Embedded 4.0 without installing it.
The good thing about this setup is that you will be "ready-to-go" as soon the Final version is released. All you will need to do will be to update the dependency and the plugin version inside your POM xml file. Now stop reading and start coding: go to my blog post "GlassFish 4 beta and Maven Embedded Plugin" and get started with Java EE 7 TO-DAY!