... ignoring the fact that you can have multiple metro apps on screen just like with any other tiling window manager.

i think there's a good argument that manually micro-managing the sizes and positions of overlapping windows (some of which can additionally be application or system modal) is a waste of time and gives few benefits.

whilst the metro apps are all pretty cut down at the moment - and there's a lot of work to do before it can viably replace the old desktop - i have no real issue with this as the direction of progress.