Joanna Stern on the Windows 8 tablet given out at the Microsoft conference:

The whole user experience feels schizophrenic, with users having to jump back and forth between the two paradigms, each of which seem like they might be better off on their own.

To be fair she notes that most of the Metro UI stuff is pretty decent (but still needs polish). The entire system seems to break down when you need to use what I will call the “legacy” UI — no surprise here.