I think the ability to "show" something is important for probably 90% of people - that doesn't mean they won't become deeply interested in programming in general, its just that they view it as a means to an end, and I think people underestimate how hard it is for beginners to make something that "works" in a cross platform way, enough to inspire them to keep going anyway.
In some ways I almost think javascript in a browser is enough, you have firebug and its shell, and you can immediately show hacking around etc..
Of course, there are some who the mathematical pleasure is really what they are after, in which case I would think haskell - and it has the bonus of a very simple syntax that really doesn't look like a "programming language" - at least what most people think.
