I have installed it, but haven't done anything with it. It wasn't what I was expecting. But then Microsoft early releases like this tend to be very rudimentary. It has promise though. Programming in C# is nice.
I wonder if one will be able to host an asp.net website from a rpi2. If so and you can have the website access the gpio pins I see lots of cool things happening.
I know it can be done with php and Apache running the linux side of RPi2, I would prefer ASP if I could. My career is in the Microsoft world so it is what I know best.