Just a month ago I wrote an entry "Where is Apple JDK6", in which I proposed an explanation for the sudden stop of releases of Apple JDK6 developer previews.
Today I read some news coming from WWDC, that proves my theory.
the fact that Java 6 will take advantage of new features only available in Leopard and the fact that the latest Java 6 preview requires the absolute latest Leopard preview confirms the suspicions many have had: First, Java 6 will not be released for OS X until Leopard ships. Second, Apple is going to continue its trend of forcing you to upgrade to the latest version of OS X if you want to use the latest version of Java.
Well, thank you Apple! As if the delay of Leopard due to some phone was not enough. :-/
One would hope that after Java went open source, it would be easier for Apple to integrate it into MacOS without any big delays. But apparently that's not the case.
Apple probably needs JDK6 as a feature of Leopard so that they can claim that Leopard has 300 new features. Without JDK6 the number would be 299 which doesn't look good in marketing presentations.