Oracle has released a new version 6, update 30, for its Java run-time environment, for Windows, Solaris, and Linux. (Apple packages and releases its own version of Java for Mac OS X.) This release incorporates stability and performance improvements, bug fixes, and support for Red Hat Enterprise Linux 6. There are no major security updates in this release. More information is available in the Update Release Notes; a list of bug fixes is also available. The most notable bug fix is for a regression in Java 6 update 29, affecting applications that use TLS/SSL; see the release notes for more details.
If you have Java installed on your system, I recommend that you install the new version, though I don’t think you need to be in a panic to do so. Windows users can use the built-in automatic update mechanism; alternatively, the new version can be downloaded here. (For some reason, the normal download location, at java.com, is still showing Java 6 update 29.)
Update Saturday, 17 December, 17:09 EST
The java.com download page has been updated to Java 6 update 30 now.