The full metal G-Shock GMB2100 series is now available for pre-orders in the U.S. at Casio.com and Reeds Jewelers. The silver GMB2100D-1A ($550) is already sold out at Casio.com, but the black GMB2100BD-1A and rose gold GMB2100GD-5A are still available for $600 each. The GMB2100D-1A is still available at Reeds, but probably not for long. Casio states an estimated release date of August 12, and Reeds states that shipping is expected in mid-August. Those in Malaysia and Singapore (where pre-orders begin at Casio.com on August 4) should take note, as GM-B2100D-1A pre-sales may sell out quickly in other countries too.
Update: The silver GMB2100D-1A is back in stock at casio.com/us and now sold out at Reeds. The black GMB2100BD-1A is sold out at casio.com/us but still available at Reeds.