Kevin: Tim Bray has a nice comparison of tablets including the Samsung Galaxy (he works for Google, and it runs Android), the iPad and mobile phones. He talks about the different ways that you'd use both a 7-inch tablet like the Galaxy and a 9-inch tablet such as the iPad. He also talks about contexts where you wouldn't want to use a tablet, such as for snapping a picture or for checking directions in a slightly sketchy neighbourhood. It's well worth reading.