I've been using it now primarily since Saturday, and while it does have its limitations, it has impressed me more than I expected. I was pretty critical of it when it was announced, but decided to wait until I used it before I came up with a final opinion.
I respect everyone's opinion in this thread but I wanted to share what I thought as I read through it. I felt more impressed with the engineers for only putting 256MB of RAM in this thing. I used to be a programmer many many years ago. In those days, folks took pride in finding a way to create a program that had the fewest lines and ran with the fewest amount of resources. I know its not so much like that anymore, but the iPad reminds me of that mindset. Now a days, computers have so much RAM, who cares if it uses a little more if its going to save you time writing your program. The iPad on the other hand is much more refreshing. The fact everything runs so fast, so smoothly, and can do so much with only 256MB of RAM, as an engineer I am really impressed with what they've achieved. Instead of just mindlessly banging out line after line as good, much more care was taken to ensure everything was optimized for the hardware.
Would it have cost them much to double that RAM? Definitely not. So I completely understand that position. Just wanted to share my thoughts as an engineer.