I think this comment is spot on. Their own bespoke XWin was replaced by X.Org in 10.5 - well strictly by XQuartz. The Apple Java runtime has already been moving closer to the standard Sun one (i.e. default renderer was switched over to Sun's a couple of versions ago).
My guess is that we'll either see Oracle take back support for shipping a version, or Apple contributing to OpenJDK (like they do with X.Org) - having A version of Java available on OS X is necessary - but for the most part it is as a web server for developers, not for native GUI development - and it is the latter point where the differences are.
(Also doesn't SWT use a different approach to the same native look-and-feel end?)
While no one uses Flash for the language, there are a lot of (non-developers) out there who use Flash (MX,CS4 or whatever it's called this week) to produce animation, etc - and we're still a long way of having a similar set of tools that produce 'browser native' content.
Considering that the CPU usage on a Mac is lower than the Flash version of the same demo, that perhaps says a lot about the prospects of Flash on mobile devices . . .
My guess is that we'll either see Oracle take back support for shipping a version, or Apple contributing to OpenJDK (like they do with X.Org) - having A version of Java available on OS X is necessary - but for the most part it is as a web server for developers, not for native GUI development - and it is the latter point where the differences are.
(Also doesn't SWT use a different approach to the same native look-and-feel end?)