yes I agree the trailers for the books are very badly made that I have seen for the adult ones but the kids ones are good. But I havent seen any on tv before only online, But it seems alot of publishers are doing them now so maybe tv is the next step, hopefully they will get better before they put them on tv!
But yes I do agree with every one on the sense that when you read a book its up to you what you picture as in places and people. But this being sais the most book trailers that I have seen don't show characters they are usally just images. But now I've seen a few adult book trailers and they don't really work but but hopefully the kids ones will take off.