These releases are well tested and appropriate for production use. M2 is the lastest IPMC ratfied release from Qpid.
If you have any questions please mail the user list user list
These releases are intended for testing and previewing new features. They have been tested and meet reasonable quality standards.
As Qpid tracks AMQP working group public work agressively it might be worth mailing the dev list to check the state of svn trunk and if you want to use that to understand the current compatibility matrix.
RPMs for the builds of trunk that have passed all the tests get automatically posted and are available at http://rhm.et.redhat.com/download
The M1 release: