For me, the buttons are big improvement over stroking or tapping the glass (those page-turn methods are retained in the new Kindle). I grip my Paperwhite with four fingers on the back and my thumb in front, so I turn pages by stroking the glass with my thumb. A mild case of arthritis in the base of my thumb joints renders this motion not exactly painful, but uncomfortable enough to be distracting. I can squeeze the page-forward button without moving my thumb at all, and I need to slide it up just about an inch to reach the less-frequently used page-back buttons.
One thing I should point out, especially for people like me who don't take enough time to read a user manual: You need to press down slightly on the buttons to make them work. Tapping, as you might do with the trackpad on your laptop, won't work — at least not reliably.
Thinner and lighter, but only a little
Compared to the Paperwhite, the Kindle Voyage is slightly thinner (0.30 inches versus 0.36 inches) and slightly lighter (6.3 ounces versus 7.3 ounces). Amazon moved the power button to the back of the device, which makes it easier to find and manipulate than the tiny button that's on the bottom of the Paperwhite. It still relies on a micro USB cord for charging, and Amazon still includes a USB cable but requires you to buy the power adapter separately.
I don't know how much profit Amazon makes on the Kindle Voyage, but they must be making a killing on protective covers at $45 a pop ($60 if you want leather). The cover is brilliant, though, consisting of a tray with strong magnets that hold the Voyage it in a very tight grip (the e-reader's rear panel is fabricated from magnesium), and a thick flap that protects its display.
A set of strong magnets in the flap holds it securely to the Voyage's front bezel when closed, and to the magnesium back when you flip it over the top to read. Push up in the middle of the bottom edge of the flap, and it folds origami style to make a prop-stand for reading. That's a whole lot better than leaning it against a coffee cup.
Cover the display when you're done reading, and the ambient light sensor immediately puts the Voyage into sleep mode. Open it back up, and the device comes fully back to life before you've completed the motion. There's really never any need to push the power button. Third parties are offering less-expensive covers, which I haven't reviewed, and I imagine the price of Amazon's covers will drop as the Voyage's newness wears off (although that could be a while. This review was written on October 23, and Amazon's website indicates it won't have units in stock until November 24).
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