I like the Notification Center in Mountain Lion, especially because it doesn't notify you of events that happen in the app you're already focused on. But what if it also had the option to ignore events that you can see? For example, I'm in Safari right now. My friend is talking in iChat (or Messages in ML) on the right. Why should iChat get a "new message" badge for the messages even though I can already see them? It would be cool if it just knew which parts of the screen you can see. This might not work for all apps, but Messages could benefit from this.