Microsoft has announced that they will launch both Windows Server 2012 R2 and Windows 8.1 on October 18, 2013!
Official annoucement by Brad Anderson:
Mark Your Calendars for Oct. 18: The R2 Wave is Coming!
“…As some of you may have already noticed, earlier this morning Microsoft announced that Windows 8.1 will be available to consumers and businesses worldwide on October 18, 2013.
But before you start your 8.1 party (with a DJ in a data center, for example), there’s even more good news:
I'm excited to announce that, on the same day, eligible customers will be able to download Windows Server 2012 R2 and System Center 2012 R2, as well as the latest update to Windows Intune! We’ll make evaluation versions available through the TechNet Evaluation Center, and these products will be available for new purchases when they hit the price list on November 1st..”