First of all, I think it's a very clean, nicely-designed site. It's a good example of how Tiki often needs to be trimmed down to be used best. I like all the little custom details like the pagetitle images, the consistent style throughout, etc.
The overall organization seems good to me, and the way people are invited to use the site to collaborate and so on. But I'm still thinking maybe there could be more focus. For example, in the center of the front page there's a list of terms that describe aspects of content. I thought clicking on one would take me to a page describing it, but instead it went to a directory page where all the links were external. I guess these are examples of the term, but the focus seemed to diffuse rather than concentrate.
I had a little trouble in the beginning just getting a handle on what the site is about, I guess because "content" is such a broad topic. After checking out a few articles, though, I got the idea but, maybe I'm slow, I would still like to see more explicit definitions or case studies or something up front to really capture the site's purpose.
My criticisms are mostly nit-picking, really, because basically the site seems to look and work very well. When I get time, I'll look again.