This week's giveaway is in the EJB and other Java EE Technologies forum. We're giving away four copies of EJB 3 in Action and have Debu Panda, Reza Rahman, Ryan Cuprak, and Michael Remijan on-line! See this thread for details.
X stands for eXtension. Any "X" parameter is vendor-specific, and unlike the other options isn't guaranteed to be available on all JVM implementations - for example, IBM's jikes or the open-source IcedTea VMs.
Customer surveys are for companies who didn't pay proper attention to begin with.