As a hobby I write some music which I publish independently on Spotify and some other platforms such as iTunes.
I use a service called http://www.tunecore.com/ and apart from their charges I have no middle hands whatsoever.
My songs seem to average nearly 4 times as much revenue as Anssi Kela's. I get around $0.008 per Spotify stream (slightly different payments apply depending on in which country a Spotify user plays a song). Here are some stats for one of my songs:
Month Streams Total
Aug 2013 670 $5.41
Jul 2013 616 $4.92
Jun 2013 561 $4.51
May 2013 608 $4.38
Apr 2013 825 $6.16
Mar 2013 1,333 $9.46
Feb 2013 990 $7.46
Jan 2013 1,123 $8.51
My take on the process is that I see Spotify as a way for me to make music publicly available on the same terms as the major publishers. As an independent musician this is a god send.
As for compensation, in the digital era where no one (this includes publishers and independent musicians) can expect big money per song sale or stream, I think what I earn from streams is very reasonable. It should be noted of course that the revenue for the example listed above are peanuts, but should I now publish as song which will become a hit, I have a viable method of reaching my audience and still earn some money from what is essentially just marketing of my music.