HTC unveiled the HTC Touch Diamond, a Microsoft Windows Mobile 6.1-based smartphone that is 3G-enabled. HTC said it has sold more than 3 million Touch handsets in the 10 months since it launched.

Often compared to Apple’s iPhone, HTC launched the Touch nearly a month before the iPhone and has now beat Apple to the 3G punch.

“Today, we mark a new era in mobile phone evolution, an era where beauty and size integrate with uncompromising innovation at broadband speeds,” said Peter Chou, president and CEO of HTC, in a statement. “The HTC Touch Diamond will make browsing the Web and using Web-enabled applications just as practical and easy to use as making calls.”

HTC also said it revamped its touch screen technology, called TouchFlo, to give screen images a 3D effect, and that the Touch Diamond introduces a new innovative touch-sensitive control for interacting with the handset.

3G capabilities are based on HSDPA 7.2 Mbps and HSUPA. Other features include a customized YouTube application, 3.2-megapixel camera with video calling, GPS, Wi-Fi, Bluetooth and 4 GB internal storage, 256 MB flash and 192 MB RAM.

The HTC Touch Diamond will be available across all major European carriers in June, followed by Asia and the Middle East later this quarter. The North American and Latin American versions of the Touch Diamond will be available in the second half of 2008.