ActiveMQ 5.7 made a big splash in October of last year with Java 7 support and secured broker connectability for the REST API.
For the 5.8, you can expect another big new feature: a REST management API
Here's the lowdown from the wiki:
Starting with version 5.8 we provide a REST management API for the broker. Using Jolokia JMX-HTTP bridge it's possible to access all broker metrics (like memory usage) and execute management operations (like purging queues) using REST API. By default the management API is exposed at http://localhost:8161/api/jolokia/ URL. So you can for example get basic broker data withwget --user admin --password admin http://localhost:8161/api/jolokia/read/org.apache.activemq:type=Broker,brokerName=localhost
or to be more specific, total consumer count withwget --user admin --password admin http://localhost:8161/api/jolokia/read/org.apache.activemq:type=Broker,brokerName=localhost/TotalConsumerCount
For more information on Jolokia protocol, see its reference manual. An API like this makes it easy to script monitoring and management operations agains the broker.
Also, don't forget to keep up with Apache Apollo, a next-generation, high-performance, multi-protocol messaging broker built from the ground up to one day be a drop-in replacement of ActiveMQ 5.x.