Java 9 (next)
New Java version is under development. Preliminary JDK versions and information can be found at https://jdk9.java.net/
Java 9 general availability is planned for September 2016.
Java 8 (current)
Java 8 is the current Java version.
Java 8 JDK/JRE update 65/66 (8u65/8u66) has been released. In addition to several fixes, this release does include additional currencies (fund codes) support. Release 66 bug fixes set is bigger.
Complete release notes can be found here.
JDK 8 can be downloaded here.
Java 7 (end-of-life)
Java 7 79/80 is the last public release. Updates are available for Oracle commercial customers only.
JDK 7u80 can be downloaded from Java 7 Archive downloads.
Java 6 (end-of-life)
Java 6 45 is the last public release. Updates are available for Oracle commercial customers only.
JDK 6u45 can be downloaded from Java 6 Archive downloads.
After the 8u11 release on mid of July, Oracle has released JDK 8u20 which includes several new and updated tools and a significant amount of bug fixes.
Java Mission Control has been updated to version 5.4. JMC is a tool to monitor and collect data from running applications and Java run-time environments.
AMC (Advanced Management Console) is a Java applications and versions usage collector and analysis tool. It requires a commercial license.
Another commercial product is the new JRE installer for Windows which fully support MSI technology.
Nice feature for 64bit users is in the Java Control Panel where we can select to automatically update both 32bit and 64bit JRE.
Complete release notes can be found at http://www.oracle.com/technetwork/java/javase/8u20-relnotes-2257729.html
Bug fixes: http://www.oracle.com/technetwork/java/javase/2col/8u20-bugfixes-2257730.html
By the way, the famous Java 8 bugs which affected several third party tools like jRebel (see for example http://www.infoq.com/news/2014/08/Java8-U11-Broke-Tools) has been fixed. See https://bugs.openjdk.java.net/browse/JDK-8051012 for details.
New update also for Java version 7: 7u67. This version only includes the bug fix for the verifier regression (see above).
Complete release notes can be found at http://www.oracle.com/technetwork/java/javase/7u67-relnotes-2251330.html
Java 6 and previous versions are at end of life stage so they are no more updated.