My latest article on Simple-Talk was published recently.  In this article I dig into how to track allocation bitmap contention in tempdb in SQL Server 2012 using Extended Events.  The method described in this article redefines how you troubleshoot this type of problem, leveraging the advanced diagnostic capabilities of Extended Events to track the problem.

http://www.simple-talk.com/sql/database-administration/optimizing-tempdb-configuration-with-sql-server-2012-extended-events/