When you try to re-upload an existing directory (to bring it up to date with the copy on the computer) the GUI does not show duplicate files (this is good) but will upload existing songs for a second time (bad). You end up with two copies of each song without any visual indication that this is going to happen.
-Mike
Wow -- this turned out to be pretty tricky. FIDNodes autoregister themselves with the PlayerDatabase on creation, and I have to create a node to be able to look for an existing match (because it has to run through the ID3 identifier as a node). In the case of a match, I wasn't cleaning up after myself. This turned out to not be a problem if you upload LocalFiles twice (which is how I was testing it) but DID become a problem if you uploaded, synched, then uploaded again (because LocalFiles cache on filename so reference counting works properly prior to a synch). Phew. Oh well.. It appears to be working properly now.