I always buy Lonely Planet guidebooks for the destinations I go to. They are informative, organised, well laid out, list a number of activities which most visitors to the Land of the Morning Calm would be hard pressed to complete. The latest edition of the Korea guide book is no exception, and is a great introduction to this amazingly deceptive country. South Korea is full of contradictions, sprawling metropolises juxtaposed with ancient Buddhist and Confucian temples. The book helps visitors explore those contradictions. Those planning on living in the country (ESL teachers) may find it lacking after they have exhausted all the sights and activities, but for visitors staying a few months or less, and travelling around Korea (not just sticking to Seoul) will find it plenty sufficient.
I reviewed the last edition, and cross referenced the new with old, and it has been thoroughly updated, accomodations, prices, eateries, and so on. No doubt this was aided by the fact that this was one of the first travel guidebook editions to come out in Lonely Planet's new format. A previous reviewer commented on the lack of personality (for lack of a better word) in this edition of the book, and I would have to say I agree with that assessment. The older edition is a little more personable. But hey, this one still does the job, and gets you from A to B. However, note that at the time of review (mid October 2005), the guidebook has been out for well over a year, and thus is already out of date. Realistically, it was out of date that day it rolled off the printing presses, things can change quite rapidly in Korea!
My own personal recommendation for Korea highlights is that visitors should try and do a tour of the DMZ, and make sure it includes Panmunjom - it's a surreal experience, and proves the Cold War is not quite over yet. Gyeongbokgung Palace in Seoul is definitely worth a visit, and make sure you visit the museum next door. Another must see is the Buddhist temple complex Bulguksa at Gyeongju.