I really don't get this at all. People spend $30 on programming books with the hopes of learning something and don't blink an eye about it. $7 for something that removes the "this is impossibly complex" stigma that programming has to non-programmers? Please, I would have loved to have something like this when I was copy/pasting Pascal into a text editor with little idea what it was doing.
I deleted my comment because I didn't think it really added to the discussion that much, but since you've replied I might as well too.
You're right, $7 shouldn't represent any barriers. You'll spend more on the coffee you drink while playing with it. It's easily disposable for anyone who can afford an iPad.
I was just saying that I think it will, and that's a shame.