Good luck-- I share your view that coming up with better ways of playing zero-sum games is not the way to make the world a better place.
The fact that this statement is coming from the 'lead developer' of Bitcoin does NOT make me feel good about the future of the Bitcoin project. Shows a complete ignorance of markets and economics. Epic epic epic fail.

The fact that Zhou thinks that such markets are a 'zero sum game' as well means that it is a good thing he is getting out. He doesn't even understand what he created. Sad.
Gavin,
Can you respond to this?
-Charlie
I'm not Gavin, of course, but I read Zhou Tong's original and Gavin's response and basically agreed. Certainly I would not consider it a 'fail' of any sort, much less an 'epic epic epic' one.
It looked to me like Bitcoinica spent it's life as a gaggle of idiots trying to make money off one another. It was 'zero sum' to the extent that some idiots succeeded and some failed but there was (arguably) not much influence outside of that environment.
There is a legitimate business use for futures markets and (probably somewhat less so) for forex-type markets, but with a few exceptions they did not appear in the little Bitcoinica world.
Don't get me wrong...I see nothing wrong with straight up gambling platforms and to the extent that I do, it's an easy choice for me to ignore them. I also don't believe that Bitcoinica either helped or hurt the Bitcoin economy very much. If I were putting a huge amount of effort into developing the platform and it was used in this manner, however, I am sure I would feel a bit demoralized and like I was wasting my time. If that is a factor in Zhou Tong and Gavin's comments, I could certainly relate.