While there is no direct way to currently embed spotify into your WordPress blog there is a workaround using Last.FM

  • Configure Spotify (Edit/Preferences/Last.fm/Enable scrobbling to last.fm and enter your Last.fm details)
  • Install the Last.fm media player  and keep both Spotify and Last.fm running
  • Install the Last.fm for WordPress plugin
  • Configure the plugin in your WordPress blog (Appearance/Widgets)
  • Set up your WordPress template to show the widget in ie the sidebar
  • The played tracks should show up