Hot ziggity, what a book! 
 Stories upon stories, thoughts and layers, intertwined - I'm gushing. I don't think I can write a coherent review just yet. I'll come back later. 
 EDIT (3/26/2012): After about 9 months of being lazybusy, I've had my thoughts gestate long enough to write something. Here goes. 
 Cloud Atlas consists of some six stories, each set in a different time, place, with different characters, and a wholly different writing style. The 19th century section is peppered with 'ye's and 'oughts' and archaic language, the 20th century segments are each wonderful for their dialect and setting, the future segments portray a corpo-state dystopia and the slow burning embers of humanity after an apocalypse. Everything flows. The distant threads of lives cross and intertwine after the centuries, and plot lines become untangled only at the very end, in some cases. 
 This may be a bit hard to read simply due to the fact that so much is going on. It will be a stretch for the average reader, but it is more than worth it. 
 The circling epicycles of history and humanity, dazzling writing, and sincere storytelling. If I could get more stuff like this, I would be a very happy reader.