This was originally announced in 2005.

BBC News : Japan tests supersonic jet model

Quote Originally Posted by BBC
Japan's Aerospace Exploration Agency (Jaxa) has successfully tested a new design for a supersonic airliner.

An 11m (36ft) scale model was launched by rocket from the test site at Woomera in the Australian desert.

Officials at the aerospace agency said the test marked a major step forward in the development of supersonic flight technology.

When the real jet has been created, it should be able to halve the journey time from Tokyo to New York.
Japan Times : Japan, France to study superfast passenger jet to replace Concorde

Quote Originally Posted by Japan Times
Japanese and French aerospace industry groups signed an accord Tuesday in France to study a next-generation supersonic passenger aircraft that would succeed the Concorde, which was taken out of service in 2003, the Ministry of Economy, Trade and Industry said.

The next-generation airplane is expected to be equipped with 300 seats, triple the Concorde's capacity, and halve the flight time between Tokyo and New York, METI officials said.

The Society of Japanese Aerospace Companies and the French Aerospace Industries Association signed the agreement on bilateral cooperation for a three-year research project at the Paris Air Show in Le Bourget, France, according to the ministry.
The project was supposed to last 3 years. In 2008, the GIFAS and SJAC agreed to extend the cooperation period until July 2011.

METI : Extension of period of the cooperative research on supersonic technologies

A picture of the prototype can be seen in the PDF file of the announcement. It looks quite a lot like the Concorde but with wider wings and a straight nose.

No news since then. MSNBC reported in 2005 that "A new supersonic jet could be in operation by 2015". If they manage to complete it on schedule (which is doubtful in this industry) we would still have to wait at least five more years before flying from Europe to Japan in 5 or 6 hours.