My main problem with this is that Spotify utilizes the full upstream bandwidth, causing the latency to go up dramatically on connections where the upstream is limited. If they were just a little bit intelligent and limited the streaming to 90% of the available bandwidth I'd be okay with it since that wouldn't affect the latency.

Question: What is the best way to traffic shape all upstream connections on OS X? I've tried ipfw but I can't figure out a good way to e.g. limit the upload on all apps except for e.g. SSH.