At Macworld 2007 Steve Jobs showed off mobile Safari's Page switching interface, but despite the operating system as a whole crying out for similar treatment, to this day Pages haven't expanded beyond Safari. At the iOS 4 event in the spring of 2010, the iPhone added limited 3rd party multitasking and a fast app switcher interface, but rather than Pages or even an Exposé-esque grid interface, it locked to the Dock.
And as far as showing currently open apps, making those apps as visually distinguishable as possible, and making them as fast as possible to switch between, that's where iOS has remained. Even on the iPad's far larger screen.
Is it time for something more?