It would be nice to see the strongest of the various Apache contenders represented here too. Once upon a time, there was just ActiveMQ to worry about:

http://activemq.apache.org/

It's long been very popular, and has all the flexibility and enterprisey goodness you could want, but has not had a reputation for speed. However, i believe there was a release a year or two ago that significantly improved performance. I vaguely remember this being based on an infusion of technology from the Qpid project, which itself has a broker:

http://qpid.apache.org/components/java-broker/index.html

Or maybe that was what led to Apollo, which is the faster, more reliable successor to ActiveMQ, but which hasn't, er, succeeded ActiveMQ:

http://activemq.apache.org/apollo/

Or maybe i just imagined the link to Qpid.

I'm fairly hazy on how these bits of software relate, and i can't promise you there aren't more somewhere in the vast Apache mansion. Even figuring that out would be useful, never mind the benchmarks!