Your Facebook notifications work with Notification Center in Mountain Lion, and you can even update your Facebook status from within Notification Center.
While it's technically always been possible to stream (using the 360's Media Center Extender technology), the new update gives the masses who aren't yet using a Media Center box a quick and easy way to stream video to the television.
"Four days is typically not enough to complete the initial investigation of the vulnerability and thoroughly test a comprehensive update, " said Mike Reavey, director of Microsoft's security response center.