I would find it difficult to go back to using only one SmartPhone. I carry two phones (work/personal) and often use both at the same time for different reasons. Usually it's as simple as needing to look at one e-mail for reference and write another -- or I run IM on one and browse the web on another. Even though the Android phone multi-tasks it's too bulky and unusable to really jump between apps for multi-tasking mostly due to the lack of a taskbar or dock but also because the built-in apps simply aren't friendly to it. You can't "alt-tab" between two e-mail messages for example. The app simply isn't designed for that. Network redundancy has saved me a couple times too. I can be pretty confident I won't be without coverage anywhere I go.