Recently Apple has been trying to market the iPad as a computer replacement. While I think theoretically this is a good idea, it doesn't work out yet.
With the iPad hardware they are desperately clinging to using the device hand held or at table level with a bad keyboard. It would be great on a stand with a bluetooth keyboard and trackpad. But their stand keeps it at table level. A device one can love has to fill two roles: a role for concentrated dedicated productivity and a role for mobile convenience. For realistic productivity that screen has to rise, and if it did, wow, what a great computer! Just like the original Mac, only way smaller and more useful.
Apple has not carved out a functional niche for the product. They have marketed the iPad as a non-useful device. I have one and I love it, but I also have a Mac. The iPad is okay for web browsing and watching video but it kind of falls short everywhere else. The iPad comes with an implied message that you shouldn't get too many bright ideas about making it more useful.
iPads are nice, but until Apple starts letting the iPad act more like a computer, it will obviously have to be less like a computer, and therefore less functional, and less useful.