Never Let Me Go - Does the Movie Stack Up?

Many moons ago I read and really enjoyed Never Let Me Go by Kazuo Ishiguro.  I remember it as a sombre read, with a twist.  Granted it's been ages since I've read it now, but I think I remember the feeling of reading it enough to make a brief comparison.  The movie holds true to this sombre mood, but is somehow less compelling.  I didn't feel a sense of urgency to understand what was going on (to be fair, this might be because I've read the book).  The other issue that I had related to Ruth's character.  In the movie, she seemed absolutely awful.  I didn't get this sense in the book.  Perhaps her desperation translated better on paper.  At any rate, it wasn't an awful movie--but the book was just so much better.  As is often the case (though not always--Girl with a Dragon Tattoo was a fabulous movie), the book out-classed the movie.