ASP.NET vNext is looking to be a very interesting release, in part due to the way the team has changed its development process. Various components under the ASP.NET umbrella are being developed separately, and will be distributed in the form of focused libraries through NuGet. The ASP.NET GitHub account shows the way these are progressing individually.
The topic link points to a master list, compiled by Tugberk Ugurlu, which lists literature currently available about the different components in progress. There is much related reading material listed also.