The movie is called "c
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does that suggest they will be making the rest of the books? If so it seams a little strange that they are starting at book 3.
I think l, w, & w is book number 2, after prince caspian isn't it? As for making it in this order, i think its probably the smartest thing to do, same thing the BBC did with the original series actually come to think of it. They made Lion first too.
main reason I'd do it is because its the best book as far as i remember, and its a very isolated sequel. it doesn't matter that this one comes first in the scheme of things. I guess its the same reason they made Lord of the Rings and not the Hobbit first. Go for the best and come back and finish it off if its a success. Although with the hobbit the fact that they are sequels are much, much clearer (what with the whole gollum escapade).