I don't know if I missed something, or if I'm wrong, but since yesterday, I've been having notifications pop up on the top right corner of my screen, under the menu bar. There was an update for the Growl app, and a grey square popped up on the top right, informing me of it. Same happened when I finished downloading a torrent, it told me on a notification when it had finished (that has never happened before). Edit: I just realised they're not in the same style as the one's previewed on Mountain Lion. But I still don't understand why they're suddenly popping up, when it never has done before.