I've been saying from Day 1 - that I don't think the iPad is that great. It may be good for games, videos and light web browsing - but the lack of keyboard make it a difficult to do any real "work" (including homework) on. For example, I am typing this message on a "real" keyboard (not an on-screen one). I know you *can* attach external keyboards - but then we're moving more into netbook/notebook space - and if we're gonna go there - we might as well throw in a mouse, larger screen, and "real" multitasking (i.e. I can see more than one window at a time - like I am doing right now at work).
So the iPad is a good trinket - and has some good vertical applications (I use it for navigation at the help of my boat, and Netflix in the cabin) - but I don't think it's will displace the functionality of "personal computers" for "productive" applications.