I wish Pandora could buy one of these services and combine their discovery engine with the catalogues of the subscription services.
Until then, I think I'll just keep buying music.
Here's a Mix I've made, for example: http://www.audiogalaxy.com/mix/87-Guitar%20Gods/?
It was amazing back in it's (less legitimate) days. It took over from Napster but improved on it in many ways.
I love Pandora for the guidance.
WAH is available on Spotify, which is good (I used them before Spotify), but it's very niche indie discovery.
I can't select a Temptations song and expect to be then offered up a Clarence Carter or Tower of Power hit.
Only Pandora has those "skillz".