I’m late linking to this one, but Michael Johnston is right that we don’t need general purpose multitasking on the iPad. He very astutely observes that most demand for multitasking centers around music and socializing.
This is one thing I’ve been curious about. Since it seems clear Apple isn’t going to enable background processes on the touch OS – at least any time soon – I wonder if they would, instead, make it possible for developers to use specific background APIs, such as audio playback (and/or recording).