Well I finished reading Cloud Atlas last night, and although it took longer than I expected to read, it was really interesting and enjoyable to read I thought.
The "nesting doll" structure of it was unusual, and it worked out better than I expected it to. The story starts with the beginnings of six stories, finishes the sixth one, and then finishes the first five in reverse order.
My favorite story was "Half Lives: The First Luisa Rey Mystery". It was about a dangerous nuclear site, and a reporter attempting to expose these reports to the public, and the company hit-men trying to kill her. It was written in a thriller style, reminding me of some Sherlock Holmes stories or Michael Crichton novels, or various action movies I've seen such as James Bond. Naturally the story style and narrative was appealing to me, and the story itself was intriguing, so these things contributed to my liking for it.
My second favorite story was "The Ghastly Ordeal of Timothy Cavendish". It was about an old man who accidentally ends up in a nursing home, and is not allowed to leave. He nearly goes crazy at the loss of his freedom, and he plots several escapes. This story appealed to me because I identified so well with the protagonist. He values his freedom above anything else, and despite the convenience of the nursing home, he never stops fighting for the return of his freedom.
The other stories were interesting as well, and all of the stories had similar themes and plot arcs, such as the fall of society or characters, the successes of barbaric groups over more peaceful ones, and a general pessimism about the future of the world. This last commonality I take slight issue with, as I have always been an optimist about the future of the world, but still find it interesting and valuable (albeit depressing) to read the fears others have for the future.