Hi neighbor!
I actually live in little Washington, but work downtown Pittsburgh. *wave*
The free version allows you to listen to your personalized station only so many hours in a given month (not sure how many hours that is), and you can only skip a certain number of songs that you don't like. You can listen to the generic stations all you like though.
The subscription (which I think is around $25/yr) lets me listen to my personalized station all the time, have unlimited skips, create different mood channels, no commercial advertising, etc. It's well worth it for me, since I'm really selective about my music and listen for at least 9 hours a day.
Morigaine