Amazon has begun pre-orders for their Amazon Kindle 3rd Generation WiFi-Only 6-Inch E-Reader (White/Graphite) for $139 with free shipping. It’s expected to ship August 27th. The new Kindle has a 50% improved e-ink contrast over its predecessor. Dimensions are 0.34″-thick with a 6″ screen and 8.7 oz. weight. Specs include 4GB of internal storage (for up to 3,500 books and documents), 802.11n wireless, text-to-speech, Whispersync (acts as a virtual bookmark to sync your location across multiple Kindles), PDF support, USB connectivity, battery life of up to one month (with wireless off).