I wonder though, how long it takes to finish an AG book from start to finish, including the merchandising aspects. Perhaps Valerie Tripp already finished a Ruthie book, and thus is now working on an Emily?

I'm not doubting you, I'm just curious. A Kit movie seems likely, and as I understand it is all but confirmed. Merchandising is definitely easier as a movie-tie in.

I also think that the choice of Emily over Linda or Susan makes sense even if I don't necessarily agree. As mayergirl said, Susan and Linda are a sort of pair, and in a way it would be unfair to choose just one. Also, both Linda and Susan's stories would be similar to Molly's whereas Emily's would be completely different, dealing with an English view of the war, which was much harsher. Of course, that makes her English and not American, but oh well.