Another part of why I believe more in tablets then over sized phones: you’ve got more room to spare. Not to mention a bigger screen and sizes that trigger tablet UI layouts in applications.
But in the flip side tablets don’t really do phone calls that well enough you’re doing speakerphone or headsets. You do use your expensive phone for answering phone calls, right? 😉
Also the overall usage gap between my phone and tablet is such that you don’t wanna know how many incoming calls I take on my tablet instead of my phone; be it in the next room or in my pocket.