This doesn't change much, the established facebook brand and etiquette is that it's used to communicate with friends. This is also the situation that Mark said they're targeting in his startup talk a few months ago.
It isn't currently a place to reach out or meet new people.
Because of this people will (currently) be hostile to messages from people they don't know. So while you can find interesting things and actually have a search that works now - it probably won't change behavior that much.