Just in case you missed the announcement, the preview build of Windows Server 2012 R2 is now available for download. If you want to see the latest and greatest, head on over there and take a gander at the new features. All of us here in support have skin in this game, but Directory Services (us) has several new features that we'll be talking about over the coming months. Including a lot of this stuff named in the announcement:
"Empowering employee productivity– Windows Server Work Folders, Web App Proxy, improvements to Active Directory Federation Services and other technologies will help companies give their employees consistent access to company resources on the device of their choice."
Obviously this is still a beta release. Things can change before RTM. Don't go doing anything silly like deploying this in production - it's officially unsupported at this stage, and for testing purposes only. But with all that in mind, give it a whirl, and hit the TechNet forums to provide feedback and ask questions. You will also want to keep an eye on some of our server and tools blogs in the near future. For your convenience, a bunch of those are linked in the bar up top for you.
Happy previewing!
--David "Town Crier" Beach