With software greater than 4.1.9, an incremental backup can be made from the Olive. The drive can be seen in Linux and all the audio and album art files can be copied. However the name convention is crap and the tags are stored in an encrypted database, not in the audio files.
Via Ext2Fsd the backup drive can be mounted to a Windows machine. Via Olive Backup Exporter, the database is decrypted and all the audio files are copied to the provided location as ARTIST\ALBUM\TRACK – TITLE. The Album images are saved as ARTIST\ALBUM\FOLDER.
However, the tags are still not saved. Via a special beta version of Log Converter, all applicable Meta tags can be exported to a text file. With a program like MP3Tag this text file can be used to fill the tags automatically.
Please read the manual and do not be scared, most of the information is for advanced users. The program can be downloaded from here. Comments and questions (other than bugs) please via the AVS forum.