How is this different than Wikipedia?

The Big Wiki has a WYSIWYG editor, so there's no need to learn a complicated syntax to work on a page.  As you can see from the screenshot, there is also the ability to tag the page such that a user could see all wiki pages that are related. In this example, T.V. and UFC tags are being used.

WYSIWYG for Editing a Wiki Page
Note the ability to easily add a table, footnote, or style your text.