After announcing their new devices at the unpacked event on 24th Feb 2014, Samsung will release them all globally April 11th. You can currently preorder them at the website of many carrier and stores such as Radio Shack and Best Buy.
Here are the specs:
The Galaxy S5 features a
5.1-inch 1080×1920 SuperAMOLED display,
a 16MP rear camera capable of taking photos in less than a second,
wireless connections such as 802.11 ac 2×2 MIMO and 4G LTE Advance,