From GA writers' blog:
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You all have some pretty strong feelings about this. I’ve been reading your comments. STRONG feelings. Which I respect. Grey’s is in its third season and we’re doing something a little…different. It’s about time we did. Because, just as I said when you all shouted your horror about the Meredith/George sex, I remind you that we writers like to follow the characters here and we try very hard not to make story just to make story. We like to have a point. Meredith being dead is about…well, you will see what it is about next week. She was in pain, this girl. And…
…okay, I don’t want to talk about that. Meredith being dead at the end of this episode. I can’t. Not yet.
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The most interesting one to watch this episode is Derek. I don’t know if you remember that in first season, he said to Meredith: “You were like coming up for fresh air. I was drowning and you saved me.” It was good to be able to call that back (everything comes back around eventually on this show, I find) and to see what happens when Meredith is drowning. He’s not Mer’s knight in shining whatever – he gets kicked out the trauma room where Richard and Bailey are working on her. He’s forced to sit out in the hall, helpless. And he’s seeing his worst nightmare come true. Because he’s realizing: Meredith has become so important to him and the prospect of losing her is terrifying. Who is he if he isn’t the guy who rescues Mer? Who is he when he can’t save a life?