If you could stream music based on your iTunes library that would be cool.
But to get random "genre'" music like Pandora is a no go.
Pandora doesn't give "random" music in the genre....it analyzes the specific song you've asked it to build a station around...IN DETAIL....and carefully chooses other songs that share the same qualities. It's all based on the "Music Genome" project that the founder started.
Have you ever actually READ about the history of Pandora and the technology behind it? Doesn't sound like you know the first thing about how it works....at all. Personally, I'm impressed with how well Pandora works, and it gets better every month.