WinRT/Metro edit:err... I mean some comments on the touch. I'm not sure what is the name for the touch feature.
From the keynotes I observed that touch+drag operations did appear to have noticeable latency. If I ever get a touch device my criteria are quality of the panel, touch responsiveness and behaviour. Those are fundamentals of a touch interface. If those are right, I think the platform is on a good track. If those are bad, then we'll just see a bunch of marketing and apps which try to hide the issues. With sufficient momentum that can be enough to propel the platform into a success but I'm not going to be too excited about touch until I see things working better. And I suspect what I saw in the keynote didn't have to do with C++/JS/.NET but some layer in the system that interprets the touch data.