If you're not a paying member, you don't get any of that. What you do get, though, is an ad-supported, Pandora-like radio service that plays songs similar to what you're looking for. As you vote songs up or down, Spotify gets a better idea of the kind of music you're into. And in my experience, the app learns incredibly quickly. I was impressed with the song selection, to say the least. If you'd rather listen to a broader selection of music, you can fire up one of Spotify's several genre stations. Unfortunately what Spotify doesn't have are curated radio stations or alternative programming for things like sports and news. This is where a service like Slacker Premium has the upper hand.
If you're into sharing what you're listening to, then Spotify is probably your best bet, considering its tight integration with Facebook. In fact, the settings menu includes an option to show every track you listen to on your profile. Also, using Android's built-in share menu, you can share track info through Gmail, SMS, Google+, and pretty much any other app you have installed on your device.
Spotify's sound quality was great, as was its streaming stability (when connected to a reliable data signal). If you have a strong Wi-Fi signal, you can even up your sound quality to High or Extreme. You also get the same options for any songs you choose to cache on your device.