Java 1.7 Preview Edition on OSX Sep 10th, 2011 At first I thought I installed it wrong. The Java version number is: 1 2 3 4 5 $ java -version java version "1.6.0_27" Java(TM) SE Runtime Environment (build 1.6.0_27-b07-393-11M3511) Java HotSpot(TM) 64-Bit Server VM (build 20.2-b06-393, mixed mode) According to the release note, it is the one.