Thanks for link. The reason for posting was not as a result of research, it was a post we wrote as part of a presentation we did for the London Sencha Touch user group we run. I appreciate there might be other useful resources out there - and that net magazine tutorial is a good example - but we had so many requests to write up our presentation from people in the audience we created the post ourselves.
Thanks to both of you for providing very useful resources on ST theming. I've "gotten by" with poor theming practice, and had been looking for some good material to do it properly. These are great.
You're welcome, actually, the post we wrote gets more traffic than our homage so it seems there are quite a few others who find it useful. Please leave a positive feedback on the blog!