"Live-tweeting" the Oscars, if you are just watching it on TV, is an excellent exercise in redundancy. Anybody who "misses" anything that happens during the three-hour-long nationally televised marathon likely does so intentionally. All those citizen "reporters" seeking to update us and let us know that Ben Stiller "HAS BLUE PAINT ON" are not really providing much of a service. See, if I were among the millions of viewers already watching the show live on TV I'd know, in fact, that Mr. Stiller has a funny costume on. I'd have even noticed "OMG A TAIL" without your having pointed it out to me. (Though there was that first 15 minutes we in New York missed due to the standoff between ABC and Cablevision. So those "Wow, this is really boring" tweets helped to serve to make us feel as though we weren't missing anything.)
Imagine you are in a room full of people. What would be acceptable? Shouting "Jeff Bridges UPSET! RAWK!" probably would not be welcome. Especially since just about every news organization in the western hemisphere predicted a walk for the Dude.
Saying "And that's a wrap. Goodnight, all!" indicates an over-inflated sense of self-importance, usually reserved for sportscasters, creative directors, and James Cameron.
Then there are those who seek to attach themselves to an event everyone is a part of, even if they have nothing to add really. The hashtag allows the attention starved to do this. It also allows marketers to push their message to what they hope may be a willing audience. But, come on, Harvard, this is beneath you.
Sure there are some media-OCDs who used the extra platform to augment their already obsessive blogging of the live TV event. Journalist Toby Young, who also wrote about the show for The Telegraph (UK), comes to mind. He actually strove to provide instant commentary on the broadcast. Of course he's a journalist. And a spotlight whore. Calling out the broadcast's director for being an "idiot" for cutting away from the Text Dolphin sign held up by one of the crew accepting "The Cove"'s award for best documentary was more like your friend on the couch making an acerbic comment and less like your friend on the couch next to you has Asperger's.