I'm enjoying watching the transition from exclusively hobby to a mix of hobby and commercial application. I wonder if the Arduino folks ever thought their education board would become a viable commercial embedded platform.
It's not totally totally there yet, but it's getting closer.
I used to think that a lot of the fun had gone out of electronics because it had gone so far beyond taking (eg) a 555 and a handful of components and making them do something good on a PCB or veroboard. But really, things like the Arduino are today's 555s. They're a component in themselves and if you treat them as such you can have just as much, if not more, fun. And as pointed out above, their universality and the heaps of code written for them makes them just as good for professional applications.
I just finished up your blog article, Using Arduinos for Real-World Embedded Applications. Great article and thank you for including the tip about the Steampunk Springfield exhibit. I have to admit I donít know much about Steampunk but my motto is life is about continuous learning. Iím always on the lookout for cool and different exhibits and Iíll have to try to coordinate a day trip to Springfield.