One of the things that really impressed me with the demo video was the access to the file system from touch apps (and the use of open app resources as an extension of it). One of the things that I feel has been pretty detrimental to iOS is the removal of any direct access to the file system, meaning that apps can't share access to a file but have to have their own copies.
I wasn't too thrilled to see traditional Windows apps sitting next door though. Yes it's taken Apple some time to get rid of some of their legacy support, but this looks like MS is unwilling to really try and move forward. Despite the backlash they would no doubt suffer for it, at some point soon they really need to put their foot down and say "No, you cannot run 1990s software on this operating system".