As readers will know, Apple released Java 6 for 64 bit intel architectures this week.
What you may not know, is that making it your first preference in the “Java Application Runtime Settings” “Java Preference” app in Utilities, fixes a nasty app switching bug you get when using spaces.
That bug is that if you change away from a space and then change back, the Java app you had in focus has gone and it is fiddly to get back.