Java 7 Build 10 is out and it has an option in the Java Control Panel to disable Java in the browser. (Windows Control Panel -> All Control Panel Items -> Java -> Security Tab).
If you don't need Java, then you shouldn't even have it installed. If you do need Java to play a game or run an app, and it doesn't have to run in the browser, then disable it in the browser:
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“The Government of Spain will not applaud those who set the world on fire just because they show up with a bucket.” - Prime Minister of Spain, Pedro Sánchez