Google knol, Wikipedia, and the ownership of ideas

I don't know how many people even know that Google Knol exists. It's a collaborative encyclopedia, kind of like Wikipedia except that the articles are more conventionally authored: someone writes an article about a topic, and if someone else doesn't like it, the critic writes a competing piece rather than editing the first one. Rumor has it that Google will eventually share ad revenues with the authors of the articles. I hope Google puts some muscle behind promoting Knol and making it a lively complement to Wikipedia. The collective authorship of Wikipedia will always have strengths that a single-author model can't beat: one of the under-discussed miracles of Wikipedia, for example, is its ability to track fast-changing phenomena of popular culture. Wikipedia tends to be mediocre and sometimes worse, however, in areas where scholarly expertise holds sway. Scholars usually don't apply their expertise to Wikipedia, even when those scholars (like me) are generally happy to share their thoughts in public for free. When I hear of my colleagues asking students to critique Wikipedia, I sometimes suggest that part of the assignment could involve making Wikipedia better. I don't think I've hooked anoyone on the idea, however, and I admit that I might hesitate to do the same thing myself, largely because the work of the class could be undone by subsequent editors. I am therefore interested in Knol's model of having authors own articles, not only in the sense that they might someday get a little cash from them but also in that (as far as I can tell) the site doesn't let other people mess with the authors' text. In Google's system, I can more easily imagine asking a class to invest time in creating a set of linked pages--or even doing a set of Knol articles and editing a parallel set of Wikipedia articles to compare the experiences. And I can much more easily imagine myself and my colleagues writing articles of more scholarly and interpretive interest on Knol. I wonder whether any of my readers are Wikipedia devotees or critics who have opinions about Knol's prospects. Anyone?