Today Brian Harry announced that the first release of TFS 2015 Update 2 is available. It is an RC with a go-live license, which means that Microsoft will support you if you install it in production, and it will be a direct supported upgrade to RTM once it is released.
Read the full release notes for Update 2 RC1 here: https://www.visualstudio.com/en-us/news/tfs2015-update2-vs
One huge thing with the release is that Update 2 includes the new Release Management vNext feature that has up until now only been available in the service (although you can use that for on premise TFS and deployments). But now you don’t have to rely on VSTS for hosting the service, it is now part of TFS 2015 Update 2!
And of course, if you want to learn (a lot) more about hwo to implement continuous delivery using TFS 2015, with the new build and release management features, grab a copy of our latest book on the topic, Continuous Delivery with Visual Studio ALM 2015: