Alright, here it is! I’ve been using Pandora just recently and gotten to love it (yes I know, “been there done that”) and love the way it recommends similar music based on the style you like. Pandora is available for other phones and just recently they launched the first Windows Mobile version for the Motorola Q9C.
Get it here now : http://www.pandora.com/on-windowsmobile
or point your phone browser to http://www.pandora.com