Samsung has announced that it has sold 3 million units of its Galaxy S II smartphone in just 55 days. The device is expected to launch in 120 countries on over 140 mobile operators, so this number is expected to keep growing, and quickly.

Last month, we reported that the Samsung Galaxy S II saw 3 million preorders, 200,000 of which were in the company's home country of South Korea. The Galaxy S II is already on sale in South Korea and the UK, and is expected to come to North America later this month.

Samsung's long-term, worldwide ambitions for the Galaxy S II are relatively modest: 10 million units in all of 2011, which is the number it sold of the original Galaxy S in 2010. At this rate though, the company will break that number very quickly.

The Galaxy S II runs Android 2.3 (codenamed Gingerbread) and features a dual-core 1.2GHz processor. It is the first handset to offer Samsung's Super AMOLED Plus screen technology (4.27-inch display, 800x480 resolution), and is the company's thinnest phone at 8.49mm, with a weight of just 116g. The device also features an 8MP primary camera with 1080p video capture, and a 2MP camera in the front, as well as integrated NFC support on some versions. It also has BlueTooth 3.0+HS and HSPA+ connectivity.

The device's new Live Panel allows you to aggregate web, social networking, and app content to a single customizable home screen. You'll be able to switch between three adjacent home screens by simply pressing and holding on the screen. The phone will come with four new content and entertainment hubs: music, games, e-reading, and social networking.

"Announced at Mobile World Congress 2011, the Galaxy S II represents our most advanced smartphone to date and demonstrates Samsung's commitment to deliver premium, market-defining devices," JK Shin, President and Head of Samsung's Mobile Communications Business , said in a statement. "This milestone reflects the continued strong support from our carrier partners around the world who have chosen the Galaxy S II as their flagship Android device."