iPad with iOS 4.2 is almost everything we've wanted in the iPad since getting an iPhone 4, plus something we've wanted from the beginning: streaming music and video from iTunes to iOS devices with AirPlay. It's coming out in November.
AirTunes has been remade into AirPlay, which now streams more than music over iTunes—it streams video, photos and music from iTunes to devices, or from say, an iPhone to an Apple TV. The other new wireless power is wireless printing, which Steve demoed from Pages.
On the iPad, multitasking looks and works just like iOS 4 on the iPhone 4 and 3GS.