So if the last WAS version you used was 6.1, then YES, a lot has changed since then. That was back in 2006! We cover the technology stack in the book, but it basically amounts to WAS Liberty (for REST and
JEE), IBM Worklight (as a mobile gateway) and then helping you understand how to choose JavaScript frameworks (for instance, from Dojo, jQuery, etc). and design systems using all of these pieces. We also cover briefly integration into other systems and parts like doing security with DataPower and using client management systems like IBM Fiberlink's MaaS360.
Kyle