What bothers me is that it looks distinctly like Win8 wouldn't run very effectively on tablets of smaller screen sizes - even with the size it's at, for those of us who are heavy users I don't think it's even beginning to match iOS's information density - the iOS 5 homescreen should hold a lot more data than, say, the alert icons or the data 'streaming' into the panels - how often does one sit at that screen staring at it anyway?
In Windows 8 you can two apps running concurrently, but only at screen size of width of something like 1366. So many tablets won't get his functionality at all.
And multitasking on Win8 seems much worse than WP7, although that's not a scale issue. The WP7 multitasking seems better almost regardless of size.
