Saying that the iPad is "between" smartphone and laptop is disingenuous. It's actually below both of these, because it's a step backwards in user interaction and device communication. You can't use the iPad for augmented reality the way you can an iPhone or iPod touch. And why isn't there any interaction between the iPhone and the iPad? Why not forget 3G with the thing entirely and let me tether my iPhone to it? Where is the much vaunted ecosystem - why isn't there a role for iPhone/iPod to play with the iPad? You still really need to own a computer of some sort with a USB port and iTunes on it so you can sync the iPad to it, so it's not like the iPad eliminates the need to own a computer.
The iPad is basically a competitor to the Kindle and the Nintendo DSi, and it's a way to lock down content further using specialized hardware. A simpler mobile device, aimed at a market that wants as little to do with computers as possible. Really the only "innovation" here was using the larger screen size to reintroduce features into core apps and put a prettier face on them. Having more screen real estate means being able to do more with iPhone OS widgets and such, but that's about all that changed. I really, really hope that they port these core application interface changes back to Mac OS - it will be very disappointing if they don't.