A friend of mine had me look at Chickipedia. I must say that I was impressed with the way MediaWiki was made to look good.. In this website they use Semantic MediaWiki and Semantic forms. I am impressed because it hides a lot of hard stuff from the users.
It looks as good as the Wikia info boxes. What I would welcome are demonstration wikis where all the competing approaches to usability can be shown. When we test the extensions, when we ensure great documentation, we can package all these approaches so that all organisations can make up their mind of the state of the MediaWiki opportunities.