It's a little dark but you generally see how these little “workspaces” work. You click one and it pops up. Clearly the X1s they were showing last night were almost unusable — they were very slow and basically mock-ups to show off some of the features. Every time the guy pressed a window it would go to the same screen.
Incidentally, this isn't a task switcher. It's basically a way to switch wallpapers i.e. set up a screen for mail, one for media, one for porn, etc.