Deleting the files automatically is actually very difiicult. Audio files are not like text files. You can’t examine them to see if two are the same. (OK, you can compare tags and kind and size information, but even this can produce mixed results, as users of the iTunes “Show Duplicate Songs” command generally atest.) Tracks represent sound files. So, you have to listen to them. But when you get right down to it, despite the text-based nature of audio file tags, only a device with ears can be the final arbiter of what a duplicate sounds like compared to the original.
For example a duplicate could be something you’ve re ripped by mistake from the same CD, but it could also be the same track from a different CD (greatest hits CD or a compilation). Is that actually a duplicate? Which one would you delete the album track or the compilation CD track?
What Im getting at is that what you consider a duplicate and what the software designer considers a duplicate may be very different. Also the outcome of any automatic organization will depend on how accurately you tagged the files in the first place.