Slacker Radio has always been a favorite online music source: create your own station, and the Slacker system feeds you the music and artists you like. However, you were still at the mercy of the system's software to pick what you heard and when.
A few weeks ago, Slacker announced that a new on-demand feature was coming, and it looks like it's finally ready for prime time. This new feature will let you browse through their catalog of three million songs to select either a song or entire albums to add to your playlist. Your playlist can be however long you want, and you can keep it cached for future playback.
The new service will have a "back" button so you can move backwards through what's already played (don't you sometimes wish your local FM station could do that?) and the list can be played in the order created by Slacker, in what I call intelligent shuffle.
Users will only need to download the app once for all their Slacker devices, but no word yet on what this premium service will cost or when it will begin. What would you pay for on-demand Slacker?