EJB 3.1 provides subset of EJB. This subset is known as EJBLite. EJBLite is available as a part of Java EE6 Web Container. You can create local EJBs with and without interface view.
EJB 3.1 The benefit is when Web component and EJB component need to access the object for business processing, no marshaling is required. If an EJB makes changes in the object state , web component can view the changes.
The local EJBs can be packaged in a WAR file. This is called as Collocated model of Java EE 6.