On top of now being able to comment on almost everything*, you can now discuss with your friends about… ads! Like this example for Tropic Thunder, on the side of my NewsFeed yesterday, that convinced Camille ditch The Mummy in favor of this movie. You can watch the trailer directly from the sidebar and leave notes for your friends. Probably one of the best, simplest, most efficient marketing engagement tool released in a while. Of course, this opens the door to negative comments about your product, but, as InsideFacebook says, “When is the last time you heard 9 friends talk about an online ad in the same day?”.

*Sidenote to my friends and everyone else: if you want to open a discussion about a status for example, you can by clicking on Comment beside the timestamp, instead of writing on the Wall. It will start a thread, connected to the commented status in lieu of hanging out sans context among your friends’ sweet birthday wishes.