I sat next to Jimbo at a Wikipedia dinner over the summer. I begged him to put a leaderboard on Wikipedia and told him I would get AOL to sell it and host Wikipedia–for free. He declined saying there will never be ads on Wikipedia. I then explained to him in detail how that one leaderboard could make over $100m per year. I told him that they should take the $100m and give it to charity. They could help fund MediaWiki, the EFF, Firefox, and dozens of other open source projects.
Jason, as usual, is full of shit