Helen Mirren as Eleanor made me very eager to see this. And it was quite entertaining. But far too abbreviated. And once again, the screenwriters have seen fit to 'adapt' the story in a way which significantly changes it. Inkheart is a big book, so it was always going to be tough to adapt for screen, and this does show.
That said, the film rolls along briskly, the casting works very well, the story it tells works, & a friend of mine who hadn't read the book LOVED it. So I think, like Eragon, it's a film best seen BEFORE reading the book. Now you've seen the film, buy the book - it's MUCH better!