Amazon just announced the Kindle Paperwhite ereader at its Santa Monica hardware press event. The device features an all new screen includes a “light guide” layer which Bezos described as a fiber-optic-like layer that releases the perfect amount of light thats direct down at the screen (not up) exactly like ambient light. Paperwhite has 25% more contrast than previous Kindles and at 212 pixels per inch, offers 62 percent more pixels. Anticipating that users will keep the light on all the time, the company improved its power management to offer eight weeks of battery life with the light on. The new device is only 9.1mm thick — thinner than a magazine. Kindle Paperwhite offers new font management tools for both publishers and readers, offering more font choices, sizes, and formatting. One of the coolest new features is “time to read” which intelligently tracks reading speeds and predicts the time to complete a current chapter. The WiFi only model of device is priced at $119, with the 3G version coming in at $179. All three devices are available today and ships on October 1st. The ad-supported kindle won’t get the Paperwhite treatment, but will get a price drop to $69.