Pandora One is
Pandora's "premium" subscription option. Besides a higher 192kbps bitrate and other features Pandora One has just added a stand-alone desktop app. No more having to fire-up Safari just to listen to Pandora or connecting to Pandora twice to get the "mini" version of the browser interface!
Pandora is $36/year. I think that it is well worth the $$$. These days I listen to my Pandora stations more than any other audio source; iTunes is kind of languishing in my applications folder...
