The Project Mustang guys (Sun Java Standard Edition 6) have their beta 2 version out and they are heading towards a final release in late October 2006. I think this is a safer bet than the Vista wait. Danny Coward blogs about the new stuff in Sun Java Standard Edition 6 in a post called The 10 Things You Need to Know About Java SE 6.
Sun Microsystems has released a Beta 2 version of its Java Standard Edition 6, formerly known under the codename Project Mustang. Java SE 6 is the runtime environment that allows Java applications to run on desktop computers. A first beta was released last February and the application has since received a series of bug fixes, prompting the company to urge developers and enterprise users to start testing their applications on the forthcoming platform.
Beta 2 version of Sun Java Standard Edition 6 source
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