I'm about to start serious on WinRT development although I won't stop Silverlight development for a while... I think lot's of people are in the same situation. We would love to have something like Jounce at the beginning our WinRT app development. I work
on a huge Silverlight app that was started before the MVVM frameworks were mature and now is way harder to introduce them in the product.
I believe what we need for now is Jounce ported for WinRT to begin with and then add more features to winrt-jounce that make sense in Windows 8 touch/metro environment.
I just hope it comes sooner than later so we can have some sort MVVM guidance in these early stages...
In all cases thanks a lot...