It needs a filter like utorrent. I.E. Say I put my classical music on a folder and I want to sync to my phone? Well I got two gigs of music and I only needs Mozart.. Phones might only have 500 megs free but even if it did not I would not want to download 450 megs to get 15 megs of music. Now on my work PC 2 gigs would be fine. But I still like to control what music I download first so I could download Mozart Requiem 2.5 megs before having to download two gigs of music and wait for it to show up in random order. So the ability to prioritize and a checklist of files you want to downLoads a Must. Deleting after the fact and keeping a Deletion stub just wasteful of energy and bandwidth. In the case of my phone syncing a one time sync option would be nice meaning I could choose to refresh the add File list later and add and remove each time I synced up. So if I added to my home collection and forgot about the phone I would not wind up with a full phone and a HUGE WIFI Overage Bill!
