Yeah from what I can tell I really wouldn't bother editing anything in Rekordbox, it doesn't save anything but Key to the actual mp3s [via ID3] (you have to tell it to). I understand the reasoning behind this, but when it is marketed as a an organisation tool it really sucks. The alternative is just to manage your music in iTunes but 3 massive pitfalls with this are...
1. The new automatic iTunes album ratings (when you rate a track in an album) are brought across into rekordbox as track ratings
2. If you have iTunes manage your filing (which is the most logical way to have it) then if you edit some info say 'album artist' it re-files everything which means in Rekordbox it can't find it, so you have to either find each track one by one (to not lose all the analysis or info you have added in rekordbox) or you have to bring them all back in and start from scratch info and analysis wise.
3. Rekordbox has far more information tags than iTunes, so you end up, as a work around, using things like 'Genre' for 'Label' or 'Grouping' for 'Date discovered' (As date added is so unreliable)
Peace.
p.s. Also from what I can tell this forum isn't very well monitored/responded to :( its sad because they have such great products.