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.
This would be important if the String had been created using the new operator and therefore was out on the heap - not a good place to be if you want to optimize by re-using the same object in multiple places. For efficiency you might force that object into the pool using intern(). Now it is available to be referenced for any other STrings that have the same value.
"JavaRanch, where the deer and the Certified play" - David O'Meara