When first giving Legend of the Seeker a viewing, a fan of the books from which they are based (The Sword of Truth by Terry Goodkind) might instantly fall into the thought process of, "Hey, it didn't happen like that in the book!". That was my initial reaction every time something happened out of sequence of the written story, was left out, or even completely made up. I was ready to write off Seeker as just another butchered book-to-video translation.
Then I realized I was thinking wrong about the whole thing. Why waste time being mad about the inconstancies? Instead, why not think of The Seeker as 'an addition to' the main story. Or even yet, exclusive content we didn't get to 'read' about the first time around. Sure, some of the events in Seeker completely change the feel of the books themselves, but the basic storyline is true enough to form that you can -- if you allow yourself to -- enjoy the show as-is.
You still get your fill of sword fighting, good-against-evil, magic, adventure and romance. The choice of actors for the characters in most cases was well done in my opinion, though Richard does seem a bit more scrawny and height-challenged than the books depict him. Adie was spot on. Zedd is great, though he towers over the other actors. The only person who seems out of place is Chase, but I got used to it after a few episodes.
The shining gem in Seeker though is the landscape of the sets, from the opening sequence you know you are in for a beautiful and wild ride, with amazing mountain vistas and dangerous chases through ancient forests. Castles, small villages, even a quick 'bath' in a lake all make for a feel that this is indeed a world other than ours.
All in all I would highly recommend this for any fan of the books, or for fantasy fans in general. If you go in with an open mind, and are willing to disregard the less-than-strict adaptation, I think you'll find the show as enjoyable as I have.