It's a for-profit site using cleaned-up and locked-down Wikipedia articles. They do this to try to lend more credibility to online reference (more description on their faq).
Is that necessary? Do they automatically lose credibility themselves because it's an "experts control the information" profit deal? Or are they moving from 2.0 to $2.0? Time will tell. But with only 3700+ "verofied" articles, they've got a long way to go to become useful.