A quote often attributed to the physicist Niels Bohr goes, as follows:
"Prediction is very difficult, especially about the future."
However, we'll have a go at this anyway, starting with the more straightforward bits. The official ASP.NET Core roadmap lists SignalR, Web Pages, and Visual Basic support shipping after the version 1.0 Release To Manufacturing/Marketing (RTM).
After this, it is fairly safe to assume that features will be added to bring the Core line closer to the existing frameworks. This includes Entity Framework, which is currently missing some of the big features of the full EF, for example, lazy loading.
There is also the move towards the .NET Platform Standard, to enhance portability across .NET Core, the .NET Framework ...