The most prominent change in this latest release (as pertains to most GenePattern users) is a warning message that will appear when you try to run any Java app which is from an "unknown" publisher and does not have a, now required, permissions attribute.
The GenePattern team is looking into how we can address this warning such that our software will not be blocked in a future release of Java. In the mean time. you can simply check the box next to "I accept the risk..." and then click run. This should allow you to use any visualizers as before. If you have any other issues after allowing the acception, please refer to this previous blog post about Java 7 and visualizer issues. (Note that Java 7 is still not compatible with the Chrome on Mac , as Java 7 is 64-bit and Chrome for Mac is still 32-bit)