It sounds to me like she's trying to convince the fans that she is nothing like the character she played and never will be. The tone of the letter is all Carrie, though. It fits her level of sarcasm to a tee. As to whether or not she'll be in Episode 7, I doubt it. While it would be nice to see the Leia of the novels make an appearance as a full-fledged Jedi still cracking jokes with Han, it's not going to happen. It would take something miraculous for Fisher to make a full comeback to be Leia. It's just not realistic. Since recasting would be a travesty, Leia's not coming back. We can wish all we want, but that won't change anything. As a hologram with her younger voice dubbed in, maybe, but nothing beyond that. (maybe in E7 they'll say Leia died a long time ago and Han has subsequently lost contact with Luke, and Luke has to find him again in order to get some help fighting whatever new villain there is) If anyone's coming back, it'll be Hamill as Luke. He still embraces the character fully (his Twitter account shows him still tickled about being able to buy foodstuffs with his face on them) and, I beleive, could jump right back into the role without much trouble.