Software Carpentry Introduction revised and on the web

I have revised the Introduction to the Software Carpentry course. This was the easy one: no diagrams, no code fragments, no glossary entries; the rest will be harder. I'd be very grateful for feedback, comments, and corrections. (And yes, audio will follow, but not today---my nephews are playing Zombies downstairs, and juvenile shouts of, "Eat lead you undead scum!" aren't quite the background I have in mind.