I didnt like Ubroadcast, the sound quality is very nice, but there are hardly any stations on it, net along listeners. I dont like that you have to download the software first to even see what stations are available.
Its easier to set up a station on Slacker.com and make a myspace for it, and post your link in public forums, you get alot more listeners, and listener's can even skip songs, you dont need a live constant stream since you basically just customize a playlist and it stores it in the software. You could have 100 people listening at the same time, and everybody would be hearing different songs at the same time. Your PC could be turned off, unplugged, disconnected from the net, and people can still listen to your station. The only thing is you cant add imaging, or talk, but web listeners dont care about that anyway.