Pandora’s internet radio has always been one of those sites that was really cool in concept, but too inconvenient to ever go mainstream. The service was long tied to computers only, and while it eventually expanded to special internet radios and some mobile phones, it still has yet to become a household name. But with the launch of Pandora’s new iPhone app last Friday, it looks like the service is about to hit critical mass. It’s a free, mobile, digital radio station that only plays music you like and lets you skip the stuff you don’t. And it rocks.

The personalized music service employs a small army of 50 musicians to create a “Music Genome” that describes each song according to 600 attributes. Listeners input a few of their favorite artists, and the site analyzes the Genome to serve up an endless stream of recommended music.

We introduced the app last Friday, when we called it our “flat out favorite application so far”, and since then it hasn’t failed to impress. Streamed music plays flawlessly over Edge and 3G networks - during a 40 mile drive I didn