Thanks to some computer problems, I missed this last week, but it’s a great story on the impact of mobile music in the mature market of Japan. PostPlay reports on a J@pan Inc newsletter piece with details of how mobile music sales there — mainly ringtones — are more than making up for declining royalty fees from CD sales.

The post also reflects on a new survey of mobile music users. 42% said they get their music by ripping CDs to their PC, then transferring them to a memory card; 29% said they get music on their handset exclusively from KDDI’s Chaku-Uta Full download service. Of the people that transfer music from their PCs, nearly half say they’re spending less on buying CDs, but more on renting them — PostPlay correctly wonders if the increase in rentals (from which record labels earn royalties) offsets the decrease in sales. The bottom line: digital and mobile media are changing the face of the music business, particularly consumer buying habits. Companies that not only adapt to this, but embrace it, will be the ones that thrive.