Dear Griatch,
I've read your article linked above and found it not only very good but also very interesting. Coming from Interactive Fiction I often puzzle at the mechanisc of MUDs, which are so different for obvious reasons--like the "quantum tree" question examplified. I really hope to see more of these type or articles and discussions.
I had read a good book on video games emergence: Game Mechanics: Advanced Game Design, by Joris Dormans.It's a very interesting book that presents a model to plan, design, create and then code game mechanis with an eye on game emergence. The author also built a framwork to actually test the mechanics in the browser (via FLASH). On this website it's possible to see and use the Framework, and find many articles on the subject of mechanics and emergence.
I thought it might be worth sharing the links and the book title. Apart from that book, I didn't come across all that many other books on the subject, but there quite a a number of articles, but mostly of very academic nature--Dorman's book is not for math scientists or engineers.
Thanks for the article, it was appreciated.