Here is the news taken directly from their site.
December 9, 2008
Sony Ericsson joins Open Handset Alliance™
On December 9, 2008 Sony Ericsson announced the extension of its portfolio strategy to include support for the Open Handset Alliance™, committing to produce an Android™ based phone in due course.
"Sony Ericsson is excited to announce its membership of the Open Handset Alliance and confirm its intention to develop a handset based on the Android platform," said Rikko Sakaguchi, CVP and Head of Creation and Development at Sony Ericsson.
"We believe Sony Ericsson can bring a wealth of experience in making consumer focused multimedia handsets with new user experience to the Alliance drawing on the successes of the Walkman™ and Cyber-shot™ sub-brands. Sony Ericsson is a strong supporter of open operating systems and we believe the Open Handset Alliance offers an exciting opportunity for a new and unique user experience only Sony Ericsson can deliver."
Rikko Sakaguchi, CVP and Head of Creation and Development at Sony Ericsson.
Complements existing Open OS strategy
Membership of the Open Handset Alliance will complement our existing Open OS strategy which is based on the Symbian and Windows Mobile® platforms. Android is a complete, open mobile phone software stack that enables Sony Ericsson to provide the best user experience with all the latest technologies available on the Internet.
Visit the Open Handset Alliance website>>
This announcement confirms that Sony Ericsson is joining the Open Handset Alliance and that we have begun development on this platform. It is still early in the process, and we cannot yet reveal any information about any future SDK from Sony Ericsson.