You may have seen that the facebook connection is not working. If you try to connect from the spotify client you enter an endless loop where the software is asking you your email and password in order to connect.
There is an easy trick to solve that problem :
1/ Go to the Spotify web site
2/ Log in with your user name and password
3/ Click on the link "Manually enable Facebook" which is on the right column
That's it, it should work on your spotify client after rebooting it.