If you can\'t wait to get a U.S. carrier version of Samsung\'s Galaxy S III, Amazon is offering the unlocked version early. Samsung Electronics\' latest flagship smartphone is available for preorder now, and will ship June 1. There is, of course, a catch. Since the unlocked Galaxy S III isn\'t optimized for U.S. carriers, there are limitations to what networks it can run on and how fast it can go. The unlocked version is a GSM device, meaning Verizon Wireless and Sprint Nextel are out. At AT&T and T-Mobile, the device won\'t be able to tap into their respective fastest networks. At AT&T, the device will work with its speedy HSPA+ network, but not its 4G LTE one. Similarly at T-Mobile, it won\'t be able to access its HSPA+ network because of the incompatibility with the carrier\'s spectrum. The Galaxy S III is expected to follow in the Galaxy S II\'s footprints and help Samsung retain its leadership position in the mobile and smartphone markets. The Galaxy S II was a huge success, ranking as one of the top selling phones of last year, often considered second to Apple\'s iPhone 4S in popularity and brand. The Galaxy S III was unveiled to the global market at an event earlier this month. The company has only said the U.S. versions of the phone would be available in the summer. The summer release timeframe should give it a nice start ahead of the launch of the next iPhone.