Pebble and Spotify on Android
Luckily the wonderful and talented Hexxeh, of Chrome OS hacking fame, is to the rescue.
I can't try it yet because my Pebble hasn't shipped, but hopefully it will work for you lucky few who have yours.
P.S. If you care about Pebble working with Spotify you can take action here: community.spotify.com/t5/Spotify-Ideas/Add-support...
As far as I can tell the issue is not on the Pebble team's side.