I am far more positive than anyone else here it seems:
I used this book to get a better view of what the different south american countries have to offer. I did not expect a very thorough nor very detailed account of each individual country because it seems to me an impossible task to cramp a whole continent into a single book. So I agree with others that it is short on detail. But for me, not knowing much about any of the countries, it was and is an extremely helpful pointer to what each country has to offer in terms of nature, archeology and people, when the best time is to visit a certain country, how to travel through multiple countries or within a single nation and more. I now have a much more specific idea of where I would like to go (argentina or venezuala), and currently am simply looking on the internet and consulting more country-specific travel guides for more specific info. As to the style, it is very much like other LP guides (which I've used extensively in the past), lucid and very easy to navigate. Although with one that deals with an entire continent it pays to spend time on it; the info is condensed (an obvious example is los llanos, venezuela) so quickly glancing through the pages will make you miss a lot.
So if you want a thorough first glance into the south american continent, I'd most certainly recommend it.