Extended Events a.k.a. XEvents were introduced in SQL Server 2008 as a light weight monitoring mechanism to support DBA.
In SQL Server 2012 XEvents is expanded to more subsystems such as SSAS, Replication, PDW etc. So with this, you have the light weight monitoring system for SSAS.
SQL Server 2012 release includes new trace events to help users for troubleshooting processing issues. Locks Acquired, Locks Released, and Locks Waiting are new trace events included with this release.