Current car audio MP3 systems here in Japan include the entire CDDB database (well, most include at least 250,000 titles). Updates to the built-in database can be easily upgraded via a memory card (memorystick, SD, CF, etc...). Also, lots of data can be downloaded over the air (regular FM). There are many different ways to get the data into the system. There are even connections for your cellphone to download the database updates over the cellular network.
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