Oracle (finally) released Java 7 today, 4 years and 7 months after the initial release of Java 6. The previous version updates used to be on a 18 months schedule, so that makes this release 37 months late. It's getting a pretty good bashing on Slashdot, primarily for its current owner, Oracle.
New features includes syntactic sugar like Strings in switch statements; underscores in numeric literals; and type inference for generic instance creation. The Open JDK site lists the same features, so I'm guessing that means everything is open sourced already. However, it seems smaller items on my wish-list did not make it, like the Immutable annotation. (The JSR 305 has been inactive for ages, and still the only implementation is a Google Code hosted project.)
yum install java-1.7.0-openjdk java-1.7.0-openjdk-devel
sudo apt-get install openjdk-7-jre openjdk-7-jdk