Yes, that works about as well as access can be considered a database: When you only have 1 user and not more than 7 rows of data 😉 (read: no more than 7 songs)
In all seriousness: I’m psyched for the next release of Banshee which will feature this too. Depending on which rating schemes it’ll use, probably a patch for firefly will be in order. Songbird uses taglib to write the rating metadata, and that’s not without errors as well. Why this is interesting? Because taglib is also the candidate to be used from firefly itself to write metadata back to files. So any bugs that songbird catches we won’t have to worry about for firefly, some day. 😉