The Definitive OS X Yosemite Review
John Siracusa's OS X reviews are legendary at this point. With each new version of OS X, he does deep dive into all the changes and upgrades. Before sitting down to use the final version of any OS X update, I always block off a few hours to thoroughly read his lengthy review. His Yosemite review is now available for pre-order on Kindle and iBooks for only $4.99.