I think it's a "lounge room computer". Your real computer (laptop / desktop) is probably in your bedroom. But the iPad seems to be aimed at being played with in the lounge room.
i know this keeps coming up, but how would you watch movies? most video content on the web is flash based.I would use it around the house. If I'm doing development, yeah I'll use my laptop, but if I'm just watching movies and surfing the web, why wouldn't I use one? Currently it's not unusual for me to sit in bed using my iPhone and apps for internet access for an hour or so.
I would also use it in my car. I'd like to mount it on the console and hook it up via Dock Connector as my removable in-car computer for navigation, entertainment, etc.
I'm not in any rush to buy one, but if I felt like I wanted one, yeah, it wouldn't be collecting any variety of dust.