Some say that Wikia, Wikipedia-like approach to search, is not likely to succeed.

Some say that Knol, Google’s approach to open knowledge, is not likely to succeed.

My opinion is that open search is one of the most important challenges in information management, and every attempt is welcome. On the other side, I have no strong opinion about free encyclopedias – as long as they are "free as in free beer" and not as in free speech…