This week's book giveaway is in the OCPJP forum. We're giving away four copies of OCA/OCP Java SE 7 Programmer I & II Study Guide and have Kathy Sierra & Bert Bates on-line! See this thread for details.
In EJB 3.1, you can have declarative timers that are triggered at deploy time. Right now, timers have to be triggered via an invocation (say from a Servlet context listener). Personally, I would use Quartz-EJB integration right now (which is very nice and easy to use, once you get the hang of Quartz). Also, some app-servers have proprietary EJB based timers/schedulers right now.
Independent Consultant — Author, EJB 3 in Action — Expert Group Member, Java EE 6 and EJB 3.1