eMusic, the second largest music download service in the U.S., says it now is in Europe as well - and is planning to repeat its success in Asia as well, particularly in Japan. 

A wildly successful launch in Europe drove eMusic to become the first music download service in all 27 EU member states, selling 4.5 million tracks within five months, Reuters reports. It has sold more than 100 million tracks in the U.S.

eMusic's service is different from competitors' in that all tracks are available in MP3 format and can therefore be played on any MP3 media player. For that very reason major music labels are wary of making their music available via eMusic.

eMusic will likely face similar label concerns as it plans to move into Asia. Japan may represent the most growth potential, but much of the music sold there is indigenous. eMusic would need to have deals in place with Japanese labels, and it could take two years to get a system in place in Japan.