On a related note, I found an interesting project last night with a more evented slant:

http://hawtdispatch.fusesource.org/

Another tangent: it's too bad java's servlet API is defined in a blocking style. Is there a JSR to remedy that deficiency?

This doesn't actually fork a JVM process, right? It's just splitting up a calculation "unit", which behind the scenes gets mapped to different execution threads. Does that sound about right?

As I understand it, that is about it. And for that exact reason it bugs me that they call it fork/join.

Yeap, that's exactly it...

Argh, can we please stop using exponentially recursive Fibonacci as an example to parallelize? Because using a linear (or even constant-time) algorithm makes it moot.

How about a big parallel mergesort or something?

The proposed fork-join framework is actually quite awful. See here: http://www.coopsoft.com/ar/CalamityArticle.html