The other discovery is somewhat intriguing: It appears that websites in Safari will soon be able to send Notifications to Notification Center--pending user approval, of course. Each site can either prompt you for authorization, or you can deny them outright; there's also a list of sites you've approved in the past, which you can prune like the Passwords section. As there's no documentation from Apple as of yet for how one might incorporate notifications into a website, there's no way to test this feature currently, but it's an interesting addition, nonetheless. According to the preference pane, these alerts will also only pop up while Safari is open--close it, and websites will be unable to send notifications to you.
[Serenity Caldwell is a staff editor for Macworld.]