If you are using FF 3 in XP (possibly other versions (?) as well) and you install Java jre 6u10 you will find that you can no longer open the Java control panel in FF by clicking Tools>Java Console. This is a known issue as discussed here. This release seems to have many changes in how it works compared to older versions. For instance there is a Java Quick Starter, a Next Generation plug-in, and the supposed ability to patch over older versions intead of installing along side them. It seems there are also some bugs in this version that really need to be worked out. For instance some people are reporting that they have to disable the "Next Generation plug-in" to get some Java content to work and some Vista users are reporting that after unticking "Check for updates automatically" that they find it has reenabled itself again later. Also some are saying that the ability of Java to patch older installations still doesn't work with this version. Here is a long thread on another site discussing this new jre. There are no security updates included with this Java update so if you decide to wait a while to see if fixes are implemented you will be no worse off. If I had known that before updating I would have waited myself. I went ahead and uninstalled the old Java version that I had before installing this one. I also ran JavaRa after installing the jre 6u10 to get rid of any remaining traces of older versions of Java. Then I removed the new service installed with this JRE as discussed here. Also, I always disable the auto updates in Java and make sure jusched is disabled from starting with Windows.