I would expect that Oracle is having here a good chance at making Weblogic THE Java Application Server and therefore at increasing its market share. Oracle Database could benefit, too, from being first in introduction of new Java features.
I'd also expect that not all Java will be open source - Oracle will likely maintain such status for the core packages and certain others, but will close the packages where they can get a competitive advantage.
Weblogic was THE Application Server even before Oracle’s acquisition of Sun. Oracle owned it since it purchased BEA. I don’t see what additional advantage Oracle gets by acquiring open source technology. I can imagine Oracle crippling MySQL to the point it isn’t a viable alternative any more. But I don’t see Oracle gaining a whole lot from Java.. As one oracle spokesperson said, they are acquiring Sun mostly for their hardware,which could be true after all.
ORACLE always closes everything they touch.