That’s correct, as of July 13th, 2015, one of the most popular Windows Server versions has reached the end of extended support lifecycle.
Windows Server 2003 has transitioned out of extended support on 14th of July 2015
For a list of any of the Microsoft lifecycle products, start with this Lifecycle Search page. Simply search for the product you are interested in viewing the support lifecycle and see the results.
As a PFE, I still continue to see customers with many Windows Server 2003 servers in production as an Operating System. Please update your products as there are many new features to both: Windows Server 2012 and Windows Server 2012 R2 that improve the overall productivity of your data center.