You will not getting the exact same phone from all three vendors, however. Most of the basics for the model of Samsung Galaxy S II are identical: a 1.2 GHz Exynos CPU, Android 2.3 Gingerbread and 16 GB of storage.
Sprint will call it as Epic 4G Touch,While AT&T & T-Mobile will say device Galaxy S II.The phone hit the Canada market in July & now available moreover 100 countries over the world.
See also : Samsung Galaxy Tab 10.1 with 4G LTE | Samsung Galaxy Ace S5830
Samsung Galaxy S™ II, Epic™ 4G Touch will bears Dual cameras having 8MegaPixel, rear-facing camera/camcorder with auto-focus and flash that shoots HD video 1080p HD high profile and 2MP, front facing camera ideal for self-portraits or video chatting,Stereo Bluetooth Wireless Technology 3.0,Samsung Exynos™ 1.2GHz dual-core processor,4.52-inch Super AMOLDED Plus (800x480 WVGA) touchscreen display.
Sprint will be the first U.S. Carrier to Debut Galaxy S II With Samsung Epic 4G Touch selling just for $199.99 from the beginning of the September.