I followed the example as much as possible - the only changes made were in the module.xml to replace the datasource name and pool-name of MySqlDS with TestDS and I also corrected the typo share-prepared-statement should have been plural share-prepared-statements
I copied my mysql-connector-java-5.1.15-bin.jar into the [JBOSS_HOME]/modules/com/mysql/main where the module.xml resides
When I started the server, I saw the message
New missing/unsatisfied dependencies:
service jboss.jdbc-driver.com_mysql (missing)
Turns out that the jar file name used in module.xml did not end with -bin.jar like the driver jar downloaded from the mysql website. I corrected the resource-root path attribute to correctly specify the jar file name.
It's a small mistake but I'll post this anyway in case anyone else has a similar renamed driver jar to contend with.