I have thinking about writing this down for quite a while, my experiences with WeTab running Unity and gnome-shell.
Unity seems a good interface for a netbook ( I have not used this on 396.2mm laptop yet). The chink being, poor Tablet support. On install, I had setup auto-login, and was presented with the desktop and launcher. Opening up an app, and maximizing it hides the launcher, which I found really hard to find again. The scroll bar is something I was unable to find in applications, and Touch gesture has not been implemented yet for scrolling. Otherwise, a good deal.
gnome-shell is one the best interface I have seen ( I have limited exposure to KDE ) , when it comes to touchscreen devices. The toggle buttons are huge and easy target to access. The application switch is trivial, as "Activies" is always visible. Switching workspace is easy, not that it is not completely hidden off during "Window Picker mode. The notification is one thing, which I easily miss out on and consequently every action which needs my attention. I would be really happy, if I could show/hide notification from system menu's notification toggle switch.
The good about both, Tiling and "auto-maximization" of Windows works good. We could try working with a Tiling window manager on Tablet, with multiple desktop. What we would need is Thumb keybord, or a keyboard which can stick to one corner assuming we use a single hand to type.
The bad about both, we need bigger fonts and target area. X still lacks a sound multi-touch foundation in most distribution. Scrolling is still a bit painful on touch devices, without gestures such as two finger scroll. Will everyone have a multitouch device ? gnome-settings-daemon xrandr plugin should also probably rotate the Touchscreen input.