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Now, it's added popup alerts above the chat box, which instantly notify you about events such as one of your friends writing on the wall and the like. The popups appear automatically, stay up for a couple of seconds and then are gone; you can still find a list of all the notifications by clicking on the icon in the lower right corner of the screen.
Normally, I'm happy about real-time updates on Facebook; I loved the live feed and I still miss it, but this time I'm not so sure. Notifications include a lot of ads and spam from applications you've installed, and I don't want to be constantly nagged by a popup, saying that (for example) I have new SpeedDate matches.