In the inception of a an "enterprise" project the race to find a "lightweight" and "cool" framework and solution opens. EJB 3.x is neither considered as "lightweight" nor cool so the search for viable replacements begins. The alternatives turn sometimes into overbloated frameworks with zillions of jars which have to be configured with several pages of XML and deployed to a "lightweight" Webcontainer.
EJB 3.X are lighter, as their reputation, there is no XML-configuration, deployment of additional frameworks, jars etc. required. EJB 3.X integrate very well with JPA, scale well on multicore, multicpu machines, and are actually the only vendor-neutral and portable solution.
This session has real world focus and discusses best practices as well as anti-patterns with source code samples and live demos.