jordan's books got lame a long long time ago. the first 3 were interesting and then rand goes and sits in the desert for like 3000 pages. booooorrrrrrring. the characters aren't flat, but they don't change in the books, they change between the books. and really they haven't changed all that much. in fact, most of the characters are quite flat. winter's heart was a lot better but from the end of the previous book i'd expected the siege of tar valon to happen. not that i wasn't pleased with mat being half the book, he is by far the most interesting character because he is mortal, unlike rand and crew, who can't possibly be in believably danger at this point in time.
thats why martin's series is better. even if main characters aren't dying (and no, no perspective character has been killed yet... lots of big supporting ones have though) you feel like the main characters can be killed, because, guess what, they're mortal. they don't have supernatural abilities. though bran will become that way and its going to hurt the book. i sorta fear a feast of crows because of it. at least martin will wrap his series in 6 books.