According to David Flannagan, it appears so:
The detail that is most interesting to me is that the JSR-233 (Scripting for the Java Platform) implementation will be included in build 40 (in a week or two, I think). And, it will include the Rhino JavaScript engine! So every Java 6.0 application will automatically have an embedded JavaScript interpreter.
This is fantastic! I've now built two products at work that rely heavily on embedded JavaScript (also using Rhino). It's a great way to expose functionality dynamically. And a likely side-benefit of this is better documentation: nice.