[zephyrnh]

I assume the point here to send someone a message on FB with a Spotify link, so they click on it in their messages and it opens up the Spotify app. If you just want to send a message from one Spotify user directly to another in Spotify, you don't need FB messages at all, right? Spotify has a list of all your FB friend IDs already and knows which Spotify accounts each is connected to

[chillacy]

I think the use case is closer to Spotify acting as an alternative client to the messenger backend, much like Adium is an alternative client for Google Chat. Which in this case you have to trust the client. It feels grosser because Spotify isn’t just a desktop application, they could in theory have stored and mined your chats.