Pebble, the Kickstarter-backed smartwatch company, is back with new offerings.Preorders for the Core 2 Duo and Core Time 2, new Pebble watches, are now open.The Core 2 Duo resembles the Pebble 2 and offers a modernized chip, 30-day battery life, and a black-and-white e-paper screen.The Core Time 2 is bigger, colorful, made of metal, and priced higher than the Core 2 Duo.