According to CNet, Facebook is going to start charging app developers a fee to achieve 'Verified Application' status. The fee is optional, but that doesn't matter. Apps that are not 'verified' will quickly get buried by those that are. I think in hindsight people will recognize this move as one of the final death knels of the Facebook platform as we know it today.
First, they de-emphasized applications all together by relegating them to a 'boxes' page and making the stream their primary interaction metaphor (Read: FriendFeed clone). Now they are trying to lock down the platform further, raising the bar for participation and charging what amounts to a protection fee for app developers to get any real attention at all.
The fact of the matter is, an increasing number of people are finally realizing that Facebook looks very similar to Pre Internet networks, AOL, Passport/Hailstorm, and any other proprietary implementation of a platform that can and must be open.
The only platform that matters on the web is the web itself, and Facebook through its actions and inactions is helping us all learn this lesson faster than ever.