I diffed all the default config files, so maybe this answers my question... Overall, seems like most config is the same, so I'm guessing we can just copy over the old config with the following modifications:
* hornetq-jms.xml: <xa> is now specified in the <connection-factory>
* hornetq-configuration.xml: <connector-ref> syntax in the <cluster-connections> section is slightly different:
OLD: <connector-ref connector-name="netty"/>
Oh, forgot to mention, we are using standalone/clustered config.