This is a geeky topic, even for this book. Nevertheless, if you develop event tracing for Analysis Services or, develop system monitoring tools, it is worth knowing that you can now trace Analysis Services using SQL Server's Extended Events framework. This event driven framework places little demand on resources, and is easily configured and scaled, handling and routing events from the database engine to consumer applications.
An entire book could be written on this subject as it is very specialized, so rather than wasting valuable space here by giving it perfunctory treatment or just repeating what has been said, we would recommend the following resources:
Jonathan Kehayias and Bob Beauchemin have both talked at length about Extended Events at the UK SQL Server conference SQLBits. You can watch their videos at http://sqlbits.com/Sessions/Event7/opening_the_sql_server_2008_toolbox_-_an_introduction_to_extended_events and http://sqlbits.com/Sessions/Event10...