Is Ping the best free music social media?

Is iTunes Ping, the latest in music-based social media, nothing more than an excuse by Apple to get students to spend more?

In September, Apple announced iTunes Ping -- a new social media network for people who like music. It's an experiment similar to Lala.com, the music store website that was purchased (and subsequently shut down) by Apple. You can see what music your friends like, recommend music to your circle, and listen to previews of songs. Unlike Lala, however, Apple still doesn't give users the option to stream a song in its entirety once for free.

This begs the question -- is there a music-based social network that works on a college student's budget? The services are free, but all except Last.fm.com try to get users to buy music. But since the prices are the same, it's the features of the different sites that make them stand out. Let's take a look at the major players and what the pros and cons are, starting with the new guy.