For Office? Fuck. It'll never sell.
Java UI's are SLOOOOOooooooowwwwwww.
As long as they are going to eliminate X11, why not use Cocoa with an eye towards supporting Gnustep as well? Then it will work on all the free machines *and* OS X and it'll rock.
Java UI sucks. And Apple has the best VM implementation too. It still sucks though. I'm pretty sure I won't use it except to view the occasional turd document someone dumps on me.