Legends of Earthsea has a quality cast and acting -- though a cast that was largely south Asian or middle eastern might have been truer to the original story -- and also does nice things with settings, sets, and computer graphics, and could be an enjoyable TV movie in its own right, if the viewer were not aware of and comparing it to the original story.
The great shortcoming is the script and storyline, which has mangled the first two books of the Earthsea trilogy -- one of the greatest pieces of writing in the fantasy genre by one of the greatest fantasy and science fiction writers -- into a very mediocre, formulaic fantasy production with a story that bears only a passing resemblance to the original. The story suffers from a peripheral character, the Kargad king, being blown into a major character to provide a central villain, all but destroying the nuance and social complexity of antagonism in the original stories. The original stories have a strong theme of growth through the lifecourse of the central character, Ged. Collapsing the stories together and shortening the time frame has required a number of story changes which weaken this central theme. A number of changes have been made with respect to Atuan that play into a sappy, very unsatisfactory ending.
If you want cheap entertainment this is a good movie. If you want truly great stories, and fantasy reading that offers insight into your everyday life and commentary on the world, read the books instead: A Wizard of Earthsea, Tombs of Atuan, The Farthest Shore, by Ursula LeGuin. The later Tehanu continues the story of Ged, but is, IMO, less deserving of praise.
