I'm not talking of Metro or Windows Store app here. Those apps are pretty restricted in what they can access in Windows. What I mean is a regular desktop app that has no such restrictions--it can access the full file system and can launch other apps.
Such regular desktop apps need to be redesigned from the point of view of usage on a small screen Windows tablet. For example, such an app will run full screen by default because that would be most convenient on a tablet. Also, many interactions would be similar to a tiled interface of Metro or like iOs and Android but there are no such Windows controls yet for the desktop API, although third party tile controls exist from Delphi/DevExpress, etc. Are there any such guidelines from Microsoft yet for desktop applications that are primarily touch input oriented?